Palettes to consider:

Earth Tones — These colors are muted, dusty colors, and many look like they originated from various kinds of dirt. This is because, back in the day, they did. The earth tones palette includes yellow ochre, cinnabar, viridian, terre verte, raw sienna, burnt sienna, raw umber, burnt umber, navy blue, etc. Try to stay away from pure black or bright white; both are too pure for this palette. Instead, stick to charcoal colors and dark greys, and ivory whites.

Jewel Tones — Ruby, Sapphire, Emerald, Garnet, and so on. These are very luscious, saturated colors that are probably more likely to be found on furniture than in the men’s department, although there’s no inherent reason you couldn’t wear them. I can’t think of a good yellow in this palette. These can be worn with black and white quite well.

Advanced maneuver: Pick an earth tone solid shirt, and a jewel tone tie that is any color EXCEPT the complement of the color of your shirt. Complementary colors are opposites on the color wheel and the short version looks like this:

red/green
blue/orange
yellow/purple

So, for example, you could find a navy blue shirt, pair with an emerald tie (possibly with some blue or yellow highlights) and a grey jacket (not black. black + navy is not allowed). An orange tie, however, would be against the rules.

Hope this helps!