It does not matter what colours that you are using on your Pallet, you need to know them inside out!! Therefore it is reasonable to keep these colour to a minimum, without restricting your combinations. I have kept to the same colours, with very small variations for about 35 years. The first consideration in choosing these colours is the colour fast qualities of each. I have two options for each of the varieties below, one lighter in value, and one darker in value;
Warm reds, earth colours, blues, yellow or orange, greens, and of course white.
It does not matter what colours you start with, you should not change them unless you have a very good reason. This way, you will know EXACTLY what happens when you combine them in a mix. I have begun to try different colours to check that I have not been missing out on opportunities, but I usually revert back to my old friends. In fact, I have taken out three colours, that I found that I was not using.
It only remains now for you to paint with them, over and over till you know them, in every possible combination that you can. Mistakes are your friends. Wasted paint is only wasted when it goes on your painting were you should not have put it. If you throw out 95% of the paint you mix, but manage to mix the colours that you need with the other 5%, YOU HAVE WASTED NOTHING!!