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Using a carpet tucking tool (often called a stair tool or carpet awl), carefully tuck any excess carpet material into the crease where the stair tread meets the riser and along any other edges, such as where the carpet rolls over the nose of the stair. This creates a clean, sharp, and professional finish. Trim any visible excess carpet fibers with a utility knife if necessary. Finally, use your hand or a carpet brush to gently brush the carpet pile in the correct direction, blending the new patch seamlessly with the existing carpet on adjacent stairs and making the repair virtually undetectable.