Observation and technique are very important when dealing with a new subject, but so are the tools you use along the way. Using the appropriate brush according to the object’s size and shape will create a continues flow and avoid mindless concerns. This will allow you to concentrate on the impression and atmosphere. Instead of worrying how the stroke will turn out, you worry if it fits the composition, the lightning, the mood.
The most important thing in achieving a desired effect with watercolors is controlling the wetness of a certain area. It’s very important to establish the subject as quick as you can so one can focus on prolonging the wetness of the paper and create soft blendings and unique texture. I am still studying this as best as I can, it’s an adventure 🙂