I was a little nervous to try my watercolors again because there is no "white-out" for them. When using pencil, you can erase mistakes. When using oil colors, you can paint in the lights. With watercolors, you have to know where your lights are and then keep them white - if you mess up, there's no eraser.
Turns out, they're not that bad. Think back to when you were a kid and used markers. Just color where you want color, don't color where you want white.
Contrary to what some people think, you can get very dark and/or vibrant colors with watercolors. Everything doesn't have to be pale and washed out.
A nice, dark black can be made by mixing burnt sienna and ultramarine blue. Colors are more vibrant if you dilute them with less water.