(This was after thrashing through the basic approach to the text and determining the best floor plan, including actor entrances, placement of major furniture, and even locating the tulip vase that has to take a dive.)
For thematic reasons and because there are multiple references to Africa in the text - one character is writing a book on the topic - some visual reference seems appropriate... and the director (also a costume designer) just happened to have a piece of fabric with a Kente cloth pattern...
Public domain image of Kente cloth courtesy of Wikipedia
Thus giving me the most important colors for the set!
(This photo is an approximation - the actual cloth has some green and blue in it too.) This fabric will be the brightest, boldest, most important source of color on the set; other materials will pick up a few of these colors in more muted shades or, like the floor, will be more neutral wood tones that sympathize with it.