Before painting stripes on the wall, start by painting the entire wall the lightest color of the stripes. Let it dry completely. There are then only the darker stripes to add. Decide whether to go vertical or horizontal. Vertical lines can make the ceiling seem higher, while horizontal lines can make the room look more spacious. Thick stripes allow the use of a full-size roller, or thinner stripes allow the use of a mini roller.
Sherwin-Williams says that stripes less than 4 inches can seem too busy, and those thicker than 12 inches seem wide and heavy. If unable to choose, alternating wide and thin stripes can make a room seem more playful and can be used in less formal rooms, such as a recreation room. Alternating different paint finishes, such as flat and glossy stripes, can add the illusion of depth.
To ensure the stripes don't bleed into one another, use painters tape to section off where the stripes are going. Once the tape is applied to the wall, seal it by running over the edges with a flat object such as a credit card. Be extra careful while painting around the edges of the tape, using long strokes in one direction and as little paint as possible. Too much paint on tape edges makes bleeding more likely.
Remove the tape from the walls when the paint is just about dry.