If you would like to experience the process you wish to know about, do the following:
1) At your Arts & Crafts Store purchase:
   a. inexpensive tubes of water color paints (primary colors blue-red-yellow)
   b. a couple of cheap sable brushes
   c. cheapest water color pad
   d. water color pencils and a sponge
2) At home tack or tape one sheet of the paper to a board or table
3) On a paper plate, put a dab of each color you bought to make your pallet and lay out your brushes and pencils if you bought them
4) wet your sponge and saturate your paper to the point of almost causing the fibers to separate
5) grab a glass with water for your brushes, some paper towel, and q-tips
6) while the paper is still wet pick up some (not a lot) of paint with the tip of a moistened sable and lightly touch the paper.  The paint will want to flow into the water and should travel some distance.
7) Mix your primary colors on your paper plate and continue to repeat step 6
8) you'll have the idea and with effort you'll capture the wash technique
9) As with all projects, stay organized and buy a water color instruction book.  this is a great venue but having a library to research at any hour is better.