Once the room has been prepped (See Interior Painting Preparation), mix several gallons of paint together in a five gallon bucket. This is known as “boxing” paint because it allows an entire four gallon box of paint to be mixed together at the same time.
Use a brush to paint around the windows, doors, baseboard, and ceiling before rolling the walls. A high quality roller cover makes the work go faster and can result in a big difference in the finished job. While lambskin covers cost twice as much as those made from synthetic fibers, they hold more paint and are worth the extra cost. Choose a roller cover with 1/2” to 3/4” nap, since they hold more paint than smooth covers.
Professional painters often work straight out of a five gallon bucket by hooking a roller screen over the rim. Face the roller screen toward you, and load the roller with plenty of paint. Start at a corner of the room and work away from it. Once the bulk of the paint is off the roller, work back over the section you have just done to even the paint out.