Painting is something that can be done without having a ton of skill and practice, but the trickiest part of painting is keeping your lines straight along the ceiling. I’ve done a lot of painting and tried a lot of different techniques for edging. It takes a lot of practice to be able to freehand straight lines, so I don’t recommend free-handing it if you are an inexperienced painter . You can tape it off, but it is a tedious process that I loathe, so I try to avoid it at all costs. Besides, even after you’ve gone to all that effort, sometimes the paint will still bleed under the tape anyway, or worse, when you take the tape off, chips of paint might come off with it. That is aggravating to say the least. I have tried using the Sure Line Paint Edger tool and it works okay at first, but it gets gunked up fast and the lines stop being straight. So, when a friend taught me this easy technique to make my paint lines straight I was thrilled! Anyone can do this and get great results.
You will need a 10 or 12 inch drywall knife like this, and a short roller like this with a 4 or 6 inch roller cover like this. Do not use a sponge roller cover (they tear and don’t cover well) or a really thick roller cover (more likely to give you rougher edges.) The one I’ve linked to is the best. It needs to have the plastic piece on the end to have the desired effect. You can get them online or at your local home improvement store.