One of the most common questions I've got from my students is "How to get my watercolor sketches bright and vivid?" I've done quick Google research before I started to write this, and, strange enough, people talk about lightfastness, pencil underlayers, better quality paint, which is also quite important, but I haven't seen anyone telling about this super simple trick: make your watercolor and your brush wet before you start using it. Very wet!
I prefer to use a spray bottle. I richly spray clean water over my whole palette or at least over the colors I'm going to use. Then, I wait for a few minutes until the water activates the watercolor pigment. And only after that, my watercolor is ready to use. Then I put my brush into the water container and also wet it very well, ensuring that all the bristles are thoroughly soaked - from the toe (the tip of the bristles) to the heel (where the bristles meet the ferrule). Now both the watercolor and the brush are ready for use. The paint will appear vibrant and beautiful!
In this photo, you can clearly see the difference between dry paint and wet paint. It's enormous! Right?
On the left: a little bit of water on my brush and dry (not activated) paint.
On the right: very wet brush and activated paint.
If you don't have a spray bottle, you can use a large brush to drop some water in every pan. Just don't forget to clean the brush every time you touch another color. Otherwise, it will be a big mess:)