Our good friend, and really talented artist, Howard Lyon just posted a wonderful article on color theory on his blog.
Titled 'Building Harmonious Color', Howard breaks down for his readers how to achieve a a cohesive color 'scheme' for a painting in very simple, easy-to-understand terms.
If you have trouble using a limited palette, or difficulty achieving 'mood' in your pieces, this is a really good read. You can check it out: HERE