How to Successfully Paint Wet-on-Wet
When working wet-on-wet pull the brush along its length with the handle close to the surface. You get two strokes with a flat bristle brush, one side then the other, look at the brush for any paint it picked up and wipe it. Think of the brush hairs as if they were the fingers on your hand stroking the surface. This method allows wet paint to go over another (wet) color with clean results.
Tip from: Roland Weight
I paint wet-on-wet with oils with lots of impasto. To keep the texture as I add more paint, I don’t dab with a brush onto the wet paint but flick the brush sideways touching the existing paint so it pulls off the new paint from the brush rather than anything else.
Use Thinner Paint on Top
Tip from: J.B.
I have painted wet on wet in oils and now paint wet on wet with acrylics. The trick is to always use a thinner paint over a thicker one. And I usually go light colors onto dark colors.
Tip from: Rich Fotia (Painter68)
Remember, to keep the fat over lean rule with oil paint, to thin the paint with oil, not turps. — Painting Guide