I began with a small pencil sketch and a value sketch (an indication of where the lights and darks will be on the painting).
The sketch was then transferred to the painting surface, a 22" by 30" sheet of Arches cold press watercolor paper.
I then thoroughly wet the back and front of the paper using a large brush except for a few areas that I want to remain white. This took maybe 5 minutes, wetting both sides several times. When the sheen was about gone (another 5-10 minutes) I started the painting.