Picking the Right Wall Color Isn’t Easy. Here’s How the Pros Do It.

Everyone knows that paint is one of the easiest, cheapest ways to transform a room. What’s not so easy? Choosing the color.

With so many colors to choose from — and a seemingly infinite number of subtle variations from a multitude of paint companies — making a decision “can feel overwhelming,” said Brigette Romanek, an interior designer based in Los Angeles.

“But when you nail it and it’s right,” she said, “that little thing you did with that gallon of paint will completely change the space.”

Ms. Romanek — who has a new book called “Livable Luxe,” with a foreword by her client Gwyneth Paltrow, coming out in October — knows that even tiny shifts in color can make a big difference. She often favors bold, saturated colors, but even when she uses understated neutrals, she doesn’t leave anything to chance.

In her own home, she employed no fewer than 16 shades of white to create the vibe she wanted in various rooms.

“Colors affect your mood and mental health,” Ms. Romanek said. “So picking the right color is as important as picking the right sofa.”

How does she do it? Ms. Romanek was updating her primary bedroom, so we asked if we could tag along.

Assess the Room

Start by asking yourself some questions, Ms. Romanek suggested: “What is the feeling I want in this room? What do I want to do in this room?”

Your answers should help inform your color choice. Deep greens or grays may be good in statement-making spaces like lounges and powder rooms, while refreshing blues and pinks could be ideal for lively spaces like kitchens and dining rooms. For a bedroom, a soothing off-white and beige may work best. But the choice is up to you.

Ms. Romanek decided to paint her bedroom, which was previously white, with a warm shade of tan. “I want to turn it into a space that’s just cozier,” she said. “It has kind of a cavernous energy and vibe, so when you come in, I want it to feel more layered, and like a cocoon. The paint color is going to do that for us.”

Explore Your Options

Once you have a general idea of the color you’re looking for, start collecting paint chips and decks. Big paint companies like Benjamin Moore and Sherwin-Williams offer a breathtaking array of options that allow you to find just about any hue. Other companies, like Farrow & Ball, Backdrop and Clare, offer edited collections that can make the process slightly less overwhelming.

After you have a collection of paint chips, narrow the field to a handful of favorites.

Tape Up Your Chips

Tape chips of the main contenders onto the wall, so you can see them in place.

If you’ve selected the fabrics, carpets and accessories you plan to use in the room, hold them near the paint chips, Ms. Romanek suggested, so you can see how the colors work together in the space.

Paint Large Samples

From the paint chips, choose two or three favorites and buy small cans of paint for sampling.

“I like to do really large samples on the wall,” Ms. Romanek said, measuring roughly four-by-four feet each.

“I’ll require that painters do the priming and the proper two to three coats of paint on the sample, so I really get a sense of what the color’s going to be,” she said. “I don’t want to have to guess.”

This step is also a chance to review the finish. Ms. Romanek often uses a matte sheen in adult bedrooms, a wipeable eggshell finish in children’s rooms and high-gloss paint on distinctive moldings. But the shinier the finish, the more imperfections will show, she noted, so it’s important to see a sample exactly where you plan to use it.

What about those large peel-and-stick sheets from companies like Samplize — is that a good way to save time?

“They are helpful and can make the process easier. But having said that, I prefer the old-school way of putting the samples on the wall,” she said. “This way I’m guaranteed I will love the outcome.”

Choose Your Favorite

With the samples on the wall, study them at various times of day, in natural and artificial light.

“You have to live with them for a few days,” Ms. Romanek said. “You have to see them in different types of light.”

Late afternoon sunlight, for instance, tends to make colors look warmer than morning light. And some colors, like grays, are notoriously tricky and can end up looking blue, purple or green.

But after all that work, choosing the winner should be easy.

“If you take the time to look at all of these things, you will come to a decision that you’ll most likely live with for years and years,” said Ms. Romanek, who settled on Turbinado from Clare for her bedroom.

Finish the Job

It’s finally time to buy the paint and get to work. If you’ll be painting the walls yourself, keep it neat and allow sufficient drying time between coats (check for guidelines on the can), because you probably won’t be painting again for a long time.

Then move in the furniture and accessories, and relax.

“Color is important,” Ms. Romanek said. By taking your time with the selection, she added, “you can really just exhale and know it’s right.”

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