When fabric rubs against itself or another fabric, pilling is likely to happen. Pilling happens when the fibers that make up the fabric are damaged or broken. They roll together and form into clumps that look like little balls on the surface, giving fabrics, especially woolen fabrics, a worn and shabby appearance. Removing the pills and restoring the smart look of a sweater is a simple process, although it's not a permanent solution since a sweater that has pilled once will do it again.
Stretch the pilled area of the sweater gently over an ironing board.
Smooth the razor lightly across the surface of the sweater, taking care not to press into the stitches.
Brush the shaved-off pills away from the sweater surface, and frequently remove any wool fibers from the razor to keep the cutting blades clean.
Work in a small area at a time, moving the sweater around on the ironing board so you always have a flat area of the sweater to work on.
Minimize pilling in the wash by always turning sweaters inside out before putting them in the machine.
Always use a fresh, sharp disposable safety razor to avoid the blunt blades of an old razor pulling the stitches of the sweater and causing runs.