A SET OF COLORS SHOULD HAVE CONTRAST WITH EACH OTHER, and should follow the rule described on the composition page. 
Common color schemes in art works include: 
[NO HUE] - Black and white photography, basic pencil drawings, etc, focus on the range of black, white, and intermediate grays and eschew hue and saturation entirely. 
[MONOCHROME OR ANALOGOUS] - a limited color or range of colors on one area of the color wheel. The artist compensates for limited hue range with emphasis on lightness and saturation contrast. 
[COMPLEMENTARY OR DYADIC] - two core color areas opposite each other on the color wheel, such as the orange & teal mix commonly seen in films. 
[TRIADIC] - three evenly spaced color areas along the color wheel, for example yellow-green/reddish-orange/bluish-purple. 
[SPLIT COMPLEMENT] - a limited color range on one side, a broader range opposite of it. 
Often a complex color scheme with many hues and variations on those hues, is more notable for what ranges of color it excludes and minimizes, than what it includes or emphasizes. 
Usually once you have your basic hue color scheme you can create added variants - ranges of saturation and brightness within your range of hues, and [tiny amounts] of hue that doesn't fit into the color scheme of the rest of the image, which seems like a violation of the rule, but is in some cases a great way to make that particular spot stand out as a focal point. 
Note also that colors do have psychological effects (warm energizes people, cool calms them) and that color can be additive or subtractive in different cases. All the hues of light combine to form white, but adding all hues of paint together will end up with something like a dark gray or black.

If you want to see some examples of my artworks currently on sale, check the Etsy link below.
Or you could order a custom artwork through my eBay shop, also linked below. 
Finally, the third link will direct you to my art galleries on Pinterest, so you can view examples of past art items, many of which have been sold a long time ago.
The banner links at the bottom of each page include links to my own webpages, links to my storefronts/shops online, and occasional links to other [third-party] verifiably legitimate stores and services I've hand-picked, vetted, and used myself. 
That said, I'll openly disclose that when you buy something from another vendor using these links, for example, a link to Amazon.com, I will get a small fraction of the sale amount and will use that as a means of supporting and expanding the projects I'm working on here. These ads for other vendors, as well as - especially! - links to my own shops, are helping me keep these sites online and growing with new content on a more frequent basis.