I continue dipping the brush into clean water as I spread the paint around the area I want it to be.
Don't I worry about ending up with too much water to paint, thereby creating adhesion problems? Once again, it's something you learn to judge through experience. If you're new to glazing, I recommend taking a small container and mixing some paint with 50 percent water (judge it by volume), then mixing the two together thoroughly, to get a feel for it.
