Gouache
I have always painted in watercolour so I am used to painting from light to dark, being the rule of thumb for this medium. There are times I will use white gouache on its own or added to other colours in small areas to create highlights or add texture. I would like to paint with gouache, but as it can be used transparently or opaquely I am confused about how you approach the light over dark or dark over light aspect.
Sue Arnold