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Once the carpet is stretched and secured to the tack strips, you will need to trim any excess material along the walls and finish the edges. Use a sharp utility knife (with fresh blades) to carefully cut off any carpet that extends too far beyond the tack strips or that cannot be neatly tucked under the baseboards. Make sure to cut as close as possible to the wall or baseboard for a clean line. For areas with baseboards, use a stiff putty knife or a specialized carpet tucker to tuck the trimmed carpet edge securely underneath the baseboard, concealing the raw edge and providing a neat finish. Finally, use a nail gun to secure the carpet at thresholds, typically by fastening a transition strip or the carpet edge itself directly to the subfloor for a solid, trip-free transition.