Oops! I’ve cleaned so many stencil brushes that I didn’t even think about instructions. We’ll have to see if we can come up with something short and sweet that will fit on the label. At any rate, here is my method for using the brush soap.
Dip your brush into the brush soap. Rub the brush soap into the bristles. I rub the bristles in a circular, scrubbing motion in the palm of my free hand. Once you have worked the brush soap thoroughly through the bristles, rinse the soap from the brush under warm, running water. It may take more than one application of soap if there is a lot of paint in the brush. Remove excess water with a towel and allow the brushes to dry before using them again.
Paintstik color will often stain the brushes, so the brush may not return to its original color after it is washed. The only product I have found that will completely remove the stains is homemade lye soap — a gift from one of my students. Your brush may be clean, but still discolored.