Beginning at the top of the stairs, measure a stair tread or landing and transfer the measurement to the back of a piece of carpet with marker or chalk. Measure so that the carpet will be flush to the wall and curve completely over the tread. Cut carpet using a carpet knife, not an all-purpose utility knife, and a metal straightedge for the best results.
Measure, cut and secure tackless carpet strips to the back, sides and front of the tread with a hammer. Attach the carpet to the tackless strips.
Measure and cut the piece needed for the riser below the carpeted tread. Some do-it-yourselfers prefer to carpet all the treads, then all the risers. If your carpet has some bulk to it, this system will work better than proceeding tread-riser-tread-riser.
Measure, cut and secure tackless carpet strips to hold the band piece to the stair riser. Go on to the next tread or riser.