It is a good practice to do a warm-up sketch in watercolor. This way you can practice some brush strokes before getting serious about your painting. Also, I find my relationship with the paper is constantly changing. I see things I didn't notice before or a different approach may emerge which makes a lot of sense.
This practice gets me inspired to paint while calming me down at the same time. Basically, it is a form of meditation which has my utmost attention.
This watercolor is an imaginary landscape. However, it has all the elements of landscape painting. It has a sky, land and water. It even has a tree so I am loosened up and ready to paint in earnest.