Tape off door frames, windows and the ceiling line. Use the masking tape and form an edge where you want the primer to end. Lay out the drop cloths.
Pour a small amount of primer into the paint pan. About an inch will get you started.
Roll the roller into the primer. It may take a few dips in the primer to get the roller covered completely for the first time. Subsequent dips in the paint will only take one or two.
Roll the primer over the surface using a "W" and "M" motion. This motion forms a W first and then you paint over the W with the M motion. This will assure an even distribution. Continue this process until you are finished. with all of the walls.
Paint all of the areas where the roller can not reach with the paintbrush. These areas will include corners, the line by the ceiling and around windows and door frames. Allow the primer to dry before painting.