I am probably the last person who should be giving advice on colour (or value in general). I just recently delved into the world of colour and value. I almost exclusively work with line and rarely try my hand at full renderings including coloured or b&w ones.
However, I'll try to explain my process using some gif's.
1st one: Attachment 306485Attachment 306486
1. Always find a good reference picture. I usually go with something that catches my eye. If I can find a naturally lit picture with a strong light source and without any photochopping, I will use that. Although even better than reference, is from life if you can find something that interests you.
2. I start by filling my canvas with a 50-70% value.
3. After that I usually do the darkest darks, but I only make them around 90% to give me some wiggle room. These darks that I put in - as far as I can tell - are very saturated.
4. In this particular one there were not very many darks on the figure so I decided to do the lightest lights first... (but I didn't go anywhere near white)
5. Now is the complicated part. When I choose my initial colour - and I am always waaaaaaay off with this - I try to get the correct saturation, temperature and value for the dark and light side. As I said, I fail miserably at getting a close relationship, so I have a lot of tinkering to do.
6. After I get all my quick initial colours in, I focus in on a smaller scale. Try to look for areas that share a same general value and colour. For each of these smaller areas, I consciously think: "Is this the right value (no? Okay is it brighter or darker). Is this the right temperature (no? Okay is it redder, or yellower). Is this the right saturation (no? Okay is it more saturated, or less saturated)." It is VERY important to make sure you get the value right, temperature and saturation are secondary.
I have also found that unless your value is right, there will be no way you can get the right colour. If at any time you are struggling very hard and you just can't seem to nail the colour, then without a doubt your values are wrong.
7. I quit when I get frustrated which is probably why I have no finished stuff :].
Start with a dark gray canvas.
Then the darkest darks :: very saturated (but don't make them black!)
Then block in some colours.
Then tinker and keep in mind value, saturation, value, temperature, and value. (Make sure you get that value right!)
Nice studies and paintings in the last one. One thing on the second painting is the window which I assume is an outdoor setting looks more like a bright painting on the wall than an outside envirement.
Thats some blow-my-mind images.... your life drawings are ace! And your colored pieces are great, too, and, and... I don't know how to crit your work, cause honestly, I'm not skilled enough to find anything to crit. Just... post more, ok? Would love to see more!