This pattern is called the Seed of Life. There is something very soothing about coloring a mandala. Maybe it's the repeating pattern.
Colored pencils are one of my least favorite tools for putting down color. I don't feel like I have a lot of control. I'm told it takes a lot of practice to get a good even layer of color. Patience is not one of virtues so I am not sure I'll ever get enough practice to get competent with them. What is your favorite tool/method for laying down color?