A good interior paint job is often 50% preparation and 50% painting. Do not rush in preparing the surfaces in your eagerness to get at the brush or roller. If you do not prepare the surfaces properly, you'll be back with the paint brush or roller in a few months.
Is some color dominating?
When you plan with split complementary colors, you begin with a single reference color. Next, choose a color from either edge of the complementary color and use it. While the complementary color scheme is a little more obvious, this scheme can fail totally if you just use paler versions of your warm colors. By the same token, picking a a warm undertone for the main contrasting color and combining it with two cool tones will showcase the warm tone.
Better still, you don't have to spend hours getting ready and hours cleaning up afterward. Premixed paints, electric-drill attachments and self-dispensing calking guns make short work of preparation. Cleaning up is a soap-and-water job for the rubber paints, or a quick dip in special cleaners for the oils. Disposable dropcloths and paper paint pails are used once and thrown away.
If you have large holes or cracks in a wall purchase a small can of vinyl repair paste. The reason I prefer it over regular wall Spackle is that after it dries it is much harder and sands easily. You can even use it for minor wood repair in a pinch.
Treat yourself to a good lunch and forget the diet. It is amazing what some pizza or a good burger will do for the afternoon painting push.
Another idea keeping Paint Brush moist until the next paint coat is applied (but not leaving for extended periods) is leaving Brush in container, wrapping top with plastic, sticking handle out the top, and taping around the can. This resembles the Maxwell House Coffee Container mentioned earlier. If plastic and masking tape is still not available, and time between coats is not very long, take that sopping wet rag, draping over the top of paint bucket with Paint Brush still in it. This technique works best when using Latex waterborne paints.