This example shows how to build up from a basic wash (i.e. first thin paint layer) and then adding detail with stronger paint. First, apply a thin layer of permanent rose colour. Whilst it is still wet, drop a slightly stronger colour to produce a second shade.
To fade together, simply wash your brush and remove some of the water by patting onto kitchen towel, then blend the two shades together.
When dry, you can repeat this process with a stronger colour. This time adding some ultramarine blue to give the colour some depth.