The Interior Design Rules I Actually Follow (And When to Break Them)

I’ve been doing this for a long time, long enough to see countless design trends rise and fall. From tiny city apartments to big rambling houses, the one thing that never changes is this: great design isn’t about rigid rules. It’s about a handful of core ideas that just work.

Think of these as your trusted toolkit, not a set of laws. They’re the secret sauce that helps you create rooms that feel right—not just pretty for a photo, but truly functional and personal. It’s so easy to scroll through social media and think a room is transformed with a few new pillows, but honestly, the best spaces are built on a solid, thoughtful plan. I want to walk you through those foundations, focusing on the ‘why’ behind every choice, just like I would with a new apprentice.

First Things First: Getting Your Space and Flow Right

Before you even dream about paint colors or sofa styles, you have to get real with the room itself. I’m telling you, the most gorgeous sofa in the world is a total waste if it blocks the natural pathway to the door. This is where the pros always start, with the bare bones of the room.

Mapping Out Your Life

Every room has a job, and often it has more than one. Your living room might be for Netflix binges, hosting friends, and maybe a kid’s play zone. Start by figuring out what needs to happen where. Ask yourself the real questions: Where are people going to walk? Where will they sit and chat? Where can the TV go so you don’t get a glare or a stiff neck?

Your most important tool here is a simple tape measure. Seriously, a good one costs maybe $15 at Home Depot and will save you thousands. Measure everything—the room’s length and width, windows, doors, even that weird nook by the fireplace. You can sketch it out on graph paper (a classic 1/4 inch = 1 foot scale works great) or use a free online tool. By the way, there are some great free ones out there like Floorplanner, SketchUp Free, or even the IKEA home planner tool that can make this a lot easier.

Oh, and here’s my “never-skip-this” checklist before you buy any big piece of furniture:

• Measure Your Space: Get the room’s dimensions down cold.
• Tape the Footprint: Use painter’s tape on the floor to outline where the new piece will go. This helps you feel the space it will eat up.
• Check Your Walkways: Make sure you still have at least 30-36 inches for major pathways.
• Measure the Entryway: And for the love of all that is holy, measure your doorways, hallways, and stairwells! I once had a client buy a massive sectional that we literally could not get through the front door. An expensive, soul-crushing lesson in planning.

The Unspoken Rules of a Comfy Room

To make a room feel easy and not like an obstacle course, we lean on some standard measurements. These aren’t random; they come from years of seeing how people actually live in and move through a space.

• Walkways: The main traffic lanes need about 36 inches of clear space. This lets two people pass by each other without doing that awkward side-shuffle.
• Conversation Pits: Arrange seats no more than 8 feet apart. This keeps conversation comfortable, without anyone needing to shout.
• Coffee Table Gap: A classic! Leave about 14 to 18 inches between your sofa’s edge and the coffee table. It’s close enough to reach your drink, but far enough for your legs.
• The Rug Situation: This is a big one. A tiny rug floating in the middle of the room just looks sad and makes everything feel disconnected. Your rug should be big enough for at least the front legs of your sofa and chairs to rest on it. It’s what anchors the entire seating area together. As a general guide, try to leave about 18 inches of bare floor around the edges of the room.

Nailing this flow from the get-go is non-negotiable. It’s the skeleton of your whole design.

Playing with Scale and Proportion to Feel Spacious

Got your layout? Great. Now let’s talk about scale and proportion. In simple terms, scale is about how objects in a room relate to each other in size, while proportion is about how they relate to the room as a whole. Getting this right is what gives a room that balanced, pleasing feeling.

The Magic Trick for Taller Ceilings

Most of us are working with standard 8-foot ceilings, not soaring lofts. But you can absolutely create the illusion of height. It’s all about guiding the eye upward.

Here’s a quick win you can try right now: Go look at your curtain rods. Are they mounted right on top of the window frame? Take them down. Re-hang the rod 4 to 6 inches above the window frame, and extend it about 3 to 6 inches wider on each side. Then, make sure your curtains are long enough to just skim the floor. This single change creates a longer vertical line, making the window feel grander and the ceiling higher. You can find extra-long curtain panels at places like IKEA, West Elm, or even Amazon for between $40 and $100 a pair.

Low-slung furniture—like a sofa with low arms or a platform bed—also helps. By keeping the big pieces low, you leave more visible wall space above them, which makes the whole room feel airier. I like to balance this with one or two tall, skinny pieces, like a floor lamp or a narrow bookcase, to keep things interesting.

How to Layer Lighting Like a Pro

Lighting is everything. I mean it. It’s one of the most powerful tools in your kit, yet so many people just stick with that one harsh overhead light that makes everyone look terrible. A well-designed room layers light to create mood, provide function, and show off the good stuff.

I always think about lighting in three layers. You need at least two in every room, but all three is the goal.

1. Ambient Light: This is your room’s general, all-over glow. Think ceiling fixtures, recessed lights, or just great natural light. Its job is to make the room usable. Pro tip: aim for a warm color temperature, around 2700K. That’s the cozy, inviting glow of a classic incandescent bulb, not the sterile blue light of an office.
2. Task Light: This is focused light for getting things done. A reading lamp next to your favorite chair, under-cabinet lights in the kitchen, a desk lamp… you get the idea. It should be bright and direct to prevent eye strain.
3. Accent Light: This is the fun part—the jewelry of the room! It’s for highlighting things you love, like a piece of art, a cool textured wall, or a big beautiful plant. Picture lights or little uplights tucked behind furniture are perfect for this.

The real secret? Put everything on dimmers. It gives you total control to go from bright and functional to soft and moody with the turn of a knob.

Heads up! While plug-in options like floor lamps (around $75-$300) or renter-friendly plug-in wall sconces ($50-$150) are fantastic, please leave any hardwiring to a licensed electrician. Bad wiring is a serious fire hazard and just not worth the risk.

Bringing a Room to Life with Texture

Ever been in a room that was technically perfect but felt a little… cold? It probably lacked texture. A space with only smooth, flat surfaces feels sterile. Texture is what adds warmth, depth, and a sense of coziness. It’s what makes you want to reach out and touch things.

Think about a nubby wool blanket, a sleek leather chair, a rough-hewn wooden beam, and a cool marble tabletop. Mixing these different tactile surfaces is what creates a rich, layered look. It’s why I always build a physical material board, laying out fabric swatches, wood samples, and metal finishes to see how they actually feel together.

Want to add some texture without breaking the bank? Here’s an easy shopping list:

• Pillow Covers: Swap out a couple of your plain cotton covers for something with more personality, like velvet, boucle, or embroidered linen. You can find great ones at H&M Home or Target for $20-$40.
• A Chunky Throw: Drape a thick, knitted blanket over your sofa or the arm of a chair. Instant coziness.
• A Woven Basket: A seagrass or rattan basket is perfect for storing extra blankets or magazines and adds a natural, earthy element. HomeGoods and IKEA are my go-to spots for these.

Of course, be practical. That gorgeous high-pile silk rug might look amazing, but it’s a nightmare in a high-traffic area or a home with pets and kids. In that case, a durable, low-pile wool or a tough sisal rug is a much smarter (and less stressful) choice.

Placing Art and Personal Stuff with Purpose

A room isn’t really finished until it reflects the people who live there. Your art and personal objects are what tell your story. But how you display them is just as important as what you display.

The Art of Hanging Art (Without Driving Yourself Crazy)

The number one mistake I see? Art hung way too high. People tend to center it on the wall itself, forgetting that the furniture exists. You have to hang art in relation to what’s below it.

The gallery standard is a great starting point: hang a single piece of art so its center is about 57 inches from the floor. This is average human eye level, and it just works. If you’re hanging art above a sofa, leave about 6 to 8 inches of breathing room between the top of the sofa and the bottom of the frame. And try to have the artwork be about two-thirds the width of the sofa so it feels balanced, not dwarfed.

For a gallery wall, my best advice is to lay all your frames out on the floor first. Play around with the arrangement until it feels right, then take a picture with your phone to use as a guide. Keep the spacing between the frames consistent—usually 2 to 3 inches—for a cohesive look.

Good to know for renters: If you can’t put nails in the wall, don’t despair! Damage-free picture hangers like Command Strips are incredible. Just make sure to check the weight limit on the package; the heavy-duty ones can hold a surprising amount.

And Now… The Fun Part: Breaking the Rules

After all that, here’s the most important piece of advice I can give you: once you understand the principles, you have my full permission to break them. The key is to do it with purpose.

For example, there’s an old belief that you should never paint a small room a dark color. But I’ve painted tiny powder rooms a deep, moody navy blue, and it looked stunning. Instead of making the room feel smaller, the dark color made the corners recede, creating a dramatic, jewel-box effect. You’re leaning into the room’s coziness and making it a feature, not a flaw.

Understanding the foundations gives you the confidence to make creative choices, not just mistakes. My hope is that you feel empowered to create a space that’s not only beautiful and functional but is a true, authentic reflection of you.

Inspirational Gallery with Photos

One lighting mistake to avoid at all costs: Relying on a single, central overhead light. Affectionately called the

Heard of the 60-30-10 rule but not sure what it means?

It’s a timeless decorator’s trick for a balanced color palette. 60% of your room should be a dominant color (think walls), 30% a secondary color (upholstery, curtains), and 10% an accent color (pillows, art, accessories). It’s a fantastic starting point, but the real magic happens when you know when to bend it—maybe try a 60-25-10-5 for an extra pop!

The essence of interior design will always be about people and how they live. It is about the realities of what makes for an attractive, civilized, meaningful environment, not about fashion or what’s in or what’s out.

• It adds instant warmth and muffles sound for a cozier feel.
• It allows you to introduce bold patterns without painting a wall.
• It can define different zones within an open-plan space.

The secret? A well-chosen area rug. Make sure it’s large enough that at least the front legs of your main furniture (sofa, armchairs) are sitting on it. This simple move anchors the entire conversation area and makes it feel cohesive.

Matte Finish: Think of the chalky, rich surface of Farrow & Ball’s Estate Emulsion. It absorbs light, hides surface imperfections beautifully, and lends a soft, sophisticated air. It’s ideal for living rooms and bedrooms.

Eggshell/Satin Finish: This finish, like Benjamin Moore’s popular Regal Select, has a subtle lustre that reflects a little light. Its key benefit is durability and wipe-ability, making it the hero for high-traffic areas like hallways, kitchens, and kids’ rooms.

When you’re stuck for inspiration, look beyond Pinterest. Your personal style is hiding in plain sight. Analyze the color palette of a Wes Anderson film, the textures of your favorite coat, or the composition of a photograph you love. Your home should be a collage of what makes you, you—not a replica of a trending image.

A recent study found that incorporating natural elements into an interior space can increase creativity by 15% and reduce stress.

This is the power of biophilic design. It’s not just about adding a few houseplants. It’s about consciously using natural materials like wood, stone, and rattan, maximizing daylight, and choosing colors and patterns that evoke the natural world to create a truly restorative environment.

Getting scale and proportion right is what separates an amateur from a professional eye. Before your next purchase, remember these simple guidelines:

• A coffee table should be no more than two-thirds the length of your sofa.
• The height of a side table should be at or just below the arm of the sofa or chair it’s next to.
• Art hung over a sofa should span about two-thirds of the sofa’s width, hung 6-8 inches above the back.

One of the most impactful, budget-friendly updates? Swapping out generic hardware. Changing the knobs on a dresser, the pulls on your kitchen cabinets, or even the light switch plates can elevate a space instantly. Look to brands like Schoolhouse or Rejuvenation for high-quality options that feel like jewelry for the room.