Scrape any peeling paint or paint chips on wood with a paint scraper and a wire brush. Use a high-pressure steam washer if the paint is on concrete. Scrape paint from glass with a razor blade.
Use a heat gun or heat tube to heat up paint to separate it from the surface. Use just enough heat to cause the paint to soften and peel up. Scrape paint away as soon as it peels. Work in small sections at a time. Continue to scrape the paint as it peels up.
Sand additional paint from wood with coarse grit sandpaper. A belt or orbital sander can be used for large jobs. Wear a dust mask and safety glasses when sanding paint. Use steel wool to get into cracks and crevasses.
Use a paint stripper to remove hard-to-remove, stuck-on paint. Buy a paint stripper that is designed for paint type and surface. There are different paint strippers for wood, concrete and masonry, and metal. Paint a generous amount of paint stripper onto the painted surface and allow it to sit until the paint softens. Follow manufacturer instructions for duration and additional application instructions. Wear rubber gloves and a face mask when working with paint stripper.