Brush the surface of the area to strip with a stiff wire brush to remove as much loose material as possible. If stripping wood, always work in the direction of the grain to prevent cross grain scratches. Remove as much material as you can to allow the stripper the maximum efficiency.
Apply heat with a commercial heat gun to the surface to soften the paint, and follow up with a metal scraper. Use a heavy blade to avoid digging into the surface.
Paint on a heavy coat of a gel-type stripper with a paint brush. Cover the entire surface you will strip, and allow the label-recommended working time for maximum effect.
Scrape the stripper and old paint away with a chemical resistant plastic scraper. Start from the center, and work your way out. Work detail areas with quad zero steel wool to fully remove the paint from the surface. A used toothbrush works well for small details. Scrape stripper and old paint into a metal container with a lid to dispose of later.
Sand the stripped surface with a power sander. For wood surfaces, a random orbital sander gives the best results. For metal surfaces, a belt sander is the fastest way to remove any paint residue that remains to prepare the surface for the new paint. Start with a fairly coarse paper, 100-grit works well. Work in successive passes from 100- to 150- to 200-grit. Use a sandpaper that is rated for the specific substrate you are stripping.
Rinse the dust from the surface with a paint thinner for metal or mineral spirits for wood. Use a rag dampened in the solvent to rinse the entire surface of the stripped material. Allow these chemicals adequate time to evaporate before applying new paint. Consult the product label for specific drying times.