Edges are one of the most important things to consider in painting. Perfect edges require two things: steady hands and patience. The best painters know how to control the brush and the angle of the brush to get perfect edges. To do this, you will want to roll the paint brush handle between your thumb and forefinger as you paint. This will give you the best horizontal control. The vertical control comes from the angle of the brush to the surface. It should be at a right angle to the surface, just slightly tilted. This will give the best results for painting along the surface, without leaving any brush marks. You should also consider using a paint shield. It will give you the best consistency between each pass, leaving you with the most even and smooth finish possible.