Often I hear: "How do I pick colors? How do I know what works together?"
I have an easy solution to give you a start on that process. I keep this sample simple, you can expand on it and finesse it. It is a very easy step to find color schemes, what goes with what. It is not the ultimate, but it can be a spring board.
I took a photo of some wooden birds in front of a simple wall. A very average picture, it does not have to be a great photo, just one you look at and say: "I like it." I opened it in Photoshop and took sample colors with the eyedropper (I). Those I put down within a shape-selection of the marquee (M) with the bucket (K). After I had collected a large enough number of them, I duplicated them and took all the saturation out of the colors to arrive at the grey values for each of these colors.
• Enhance > Adjust Color > Hue/Saturation
That is an important step. When you combine colors and lay them on top of each other, you should be able to see them as separate grey values, there should be a distinction between them. Think about a person with poor eyesight or color blindness, they only see grey. How often have you seen red type on a black background, almost impossible to see. When you change the hue of the color, the grey value is the same. That is also good to know, because once you have determined a grey, you can shift the hue to your liking. The saturation can also be changed without changing the grey value. Only the lightness setting will change the grey value.
When you now change the hue of all these colors together, you will have automatically colors that are in harmony with each other. You can obviously add colors, or take some away, but it gives a nice and easy guide to choose colors from.