This story shows you how to properly hold a paintbrush and make good strokes for the best application.
Load the brush with the proper amount of paint (see page 53), and start your application in one corner of the wall. Holding the brush between your thumb and fingers, and keeping it at about a 30-degree angle to the wall, unload the paint from the brush with an upstroke, from 16 to 20 inches long. Flex the brush slightly so it releases the paint on the surface. (Whenever possible, paint with vertical strokes -- they will tire you less than horizontal strokes.)
Immediately set the paint on the surface with a downstroke, applying slightly less pressure than the first stroke, and holding the brush at a slightly steeper angle to spread the paint evenly. Flexing your wrist as you work will help you fall into a natural rhythm, and you will not tire as easily.
With slight pressure on the brush, smooth the applied paint with a light upstroke. While you're finishing this stroke, lift the brush slightly to feather the end of the paint line. Resist the temptation to overbrush latex paint. A few strokes is all you need to produce a level coat. Overbrushing will thin the coat and invite lapping and other problems when the paint dries.
Some painters apply paint working from an unpainted area to a painted area. Others apply paint from the painted area. Whichever method you choose, work in 2- to 4-foot sections, and always finish with a light stroke into the edge of the last painted section, then with one long continuous stroke to eliminate overlap lines and brush marks. Latex paint starts to dry fairly quickly, so adjust your application accordingly. Oil-base paints have a longer open time.