My process for digital watercolor in Procreate has evolved into something I'm consistently happy with, so I want to document it while I still remember the iterations.

The key insight: watercolor is about the edges of wet paint meeting dry paper and other wet paint. The characteristic bloom effect happens when wet paint meets wet paint. The characteristic granulation happens when pigment settles into paper texture.

I simulate these using: a textured brush with low opacity and high flow for the primary washes. The texture introduces the granulation quality. For wet-on-wet blooms I use the smudge tool at low strength on a fresh stroke before it dries.

The mistake I made for a long time: trying to simulate watercolor by thinking about the pigment. The better mental model is thinking about the water — how much water is in each stroke, and what happens when strokes of different water content meet.