Homeowners always ask me how to cut in walls and ceilings when painting a room. It’s really not that hard, and once you learn how to work the bristles of the brush you’ll be cutting in walls and ceilings, and painting trim like a pro.
You want to try and keep the bristles flat and with enough paint in and on the brush for spreading you can do it.
When you’re cutting in think of all corners, no matter how large or small, as little 90 degree angles. Whether cutting in the top of baseboard trim, the edge of door trim, the ceiling, when you dissect it down to it’s simplest form all you’re doing a resting the “bladed” bristles into a corner and pulling down, or in some cases across.
As you can see in the picture I’m only using a small portion of the formed bristles, in the corner, and sort of “whisking” my way down. Some people might find it easier to use an “angled” brush and that’s okay, just get the bristles flat. Don’t sit and play with it and peck, go long on the strokes, or as long as you can. You’ll get the hang of it.
Once you get a section “cut,” as you move along go back and brush out. This will allow enough room for rolling the rest of the walls.
When I’m training new workers I always have them start in the corners of the room and work those 90 degree angles. Once they learn that I move them to brushing around windows and doors before moving up to cutting in the ceilings. By the time they get to the ceilings they have it down.