Removing ceramic tiles from the wall without damaging the drywall underneath requires patiently removing the grout and the prying the tiles off the surface. While the tiles sometimes peel away without leaving much residue, at other times they leave behind thinset cement that requires grinding off the wall.
Look for grout removal tools at a home improvement store. Manual tools resemble an ice pick, but their design helps to prevent gouging the drywall underneath. Hold a heat gun near the seam to help to loosen the grout so you can pick it away. For faster removal, use a rotary or oscillating grout removal tool. While it is hand-held, it uses electricity to make the task less laborious.
Use a putty knife to loosen the tiles from the wall, and then gently pry them away. Some adhesives, including thinset, require breaking the tile before removing it.
To remove the adhesive residue, first determine what it is. Thinset is a concrete product, while mastic resembles thick glue. Use an oscillating tool with a rasp attachment to remove thinset. Scrape away any mastic using a wide-blade putty knife.
If the removal process causes damage to the drywall, repair it before proceeding. Patch any holes, and cover the surface with a skim coat of drywall compound. Once it dries, the wall is ready for the new finish.