Well lets dive in and talk about watercolor paints. Watercolor is an extraordinary medium and each brand of watercolor has its own uniqueness. I have three brands that are my favorites: Winsor-Newton, Schminke, and Holbein. There are colors within each of these brands that I like over the other. For example, Winsor-Newton Ivory Black performs better than Schmincke's, and Schmincke's Indian Yellow performs better than Winsor-Newton brand. I have more Winsor-Newton colors however, than the other two brands. I love to experiment with all of them. Experimenting reveals the characteristics of the paints, some mix well with each other and others don't mix well at all. By experimenting I know what colors work well together before using them on my painting. Getting familiar with your brand of paints is a good way to get to know how they'll perform.
I keep a small piece of 300 pound watercolor paper (about 5 inches square in size) on my table to actually test the color before applying it to my painting. If I don't like the look and feel of the color or mixture of colors, I try another until I'm satisfied.
Watercolor paper varies in performance also. It is best to purchase a good quality paper from the start, make sure it is 100% cotton, mold-made watercolor paper. I prefer 300-lb soft-pressed, most artist's use cold-pressed. I prefer to use soft press because I like how the watercolors work with the paper; it receives the watercolor well, much better than cold-pressed.
Its back to work. Happy Autumn!