To prepare a wall for painting after wallpaper removal, scrape the glue residue from the wall, wash the wall thoroughly, and allow time for it to dry. Check the wall for holes or damage, and make any needed repairs. Prime the wall surface, and paint the wall.
To remove large chunks of glue residue, mix a 50-50 solution of fabric softener with hot water in a spray bottle, and spray it on the glue residue. Allow it to soak for about 20 minutes, and scrape off the glue with a putty knife. Spray the wall completely with clean water to rinse it, and wipe the surface thoroughly with a wet sponge. Let it dry for a day or two.
Inspect the wall for any scrapes, crevices, holes and gouges. Fill them with a drywall sealing product, and allow the product time to dry completely. After sealing, repair the wall using lightweight or standard patching compound. Use coarse-grit sandpaper to sand the wall for a smooth finish. Change to a medium-grit sandpaper for a flat finish.
Apply two coats of primer, and allow the primer to dry completely between coats. Use suitable primer to ensure the wall surface is free of stains. Paint the prepared wall with quality paint.