I am now a craft paint junkie. I still do my test palettes, such as you see above, because as you all know the colors never dry the same color you see when they are wet.
This spring inspired painted page will soon be cut into individual squares with the brand and color placed on the back. As I'm trying to decide on what colors to use on a figure I can place the colors side-by-side easily to develop the color scheme. This helps me quickly judge what shade of a color will work best with the other tints and shades found on this page. It is sort of like creating your own paint chips from the colors you have on hand. Spray them with varnish and they will last you for years.
It's an easy little thing that I hope becomes a tool for you too!
Have fun painting!