Here is how I make my chalk paint, there are all sorts of ways this is what works best for me. I have some colors that were mixed this way over a year and they are still a great texture and ready to use.
That being said, since I made this tutorial I learned that flat house paints are amazing as chalk paint. The color choices are endless and the overall result is fantastic. I still use the same process, now I just start with flat house paint. Give it a try and let me know what you think. I would love to see your projects.
Here are the links to where I get my materials