“You don’t listen to music one note at a time, and you don’t see colors one at a time,” Ashcraft explains. “It’s all about relationships, combinations, and context.” Need examples? Here are four—in blue, yellow, green, and red—devised especially for Real Simple readers. Copy these palettes for walls, ceilings, and trim, or get inspired to create your own. To buy: Christine low round side table, olystudio.com for stores. Brompton sofa, georgesmith.com for info. Velvet II platinum pillow (large), roomandboard.com. Canvas linen pillow (small), ochrestore.com for info. Nineteenth-century Italian mirror (small, above sofa), hudsoncityantiques.com for info. Handmade Tibetan rug, dolmarugs.com for info. To buy: German porcelain pieces from the 1960s (on mantel), The End of History, 212-647-7598. Drawing by Corey Daniels, Paula Rubenstein, 212-966-8954 for info. Color Reform rug, abchome.com. “Rich greens, with a big pink bloom on top.” The soft ceiling color is also used on the upper trim to lighten up saturated moss walls, creating a cheerful canopy. An earthy dark gray-green on windows and baseboards complements the moss. “You can’t go wrong mixing most greens—just look outside.” Paint: walls, Oregano; ceiling, Pink Innocence; trim, Mohegan Sage: each from $36 a gallon, benjaminmoore.com for stores. To buy: Vintage glass bottle, Paula Rubenstein, 212-966-8954 for info. Lidded laundry basket, calypsostbarth.com for stores. Snooze chair, ochrestore.com for info. Skowhegan Quarry painting, by Robert Eaton; and side table designed by James Mont: Lobel Modern, 212-242-9075. Aldo Londi for Bitossi lamp, Cosmo, 718-302-4662. Color Reform rug, abchome.com. The effect is dramatic but—because it’s low-contrast—not shocking to the senses. When it comes to furniture, spare, clean-lined pieces keep red’s bordello risk at bay. Paint: walls, Cherry Wine; ceiling, Dry Sage; trim, Raisin Torte: each from $36 a gallon, benjaminmoore.com for stores. To buy: Danish tall oxblood ceramic vase from the 1950s, The End of History, 212-647-7598. Leger Tube stool, ochrestore.com for info. Gueridon side table, stelacollection.com for info. Georgian sofa, georgesmith.com for info. Color Reform rug, abchome.com.