Sand the wall with a medium grade sandpaper to create that rough surface for the grout.
Prep textured wall for tiling.
Scrape away any loose or peeling paint or wallpaper.
Get rid of or pre treat wallpaper if present repair any cracks or signs of damage.
Remove any remaining dust oil or grease with tsp tri sodium phosphate or an.
Drag the wide area of the scraper across the paint in all directions to remove as much paint as you possibly can.
Sand so that the adhesive can bond.
Wash the wall with tsp tri sodium phosphate or an ammonia based cleaner to remove any grease or oil.
To do so make sure all of the tiles are intact and secure.
Remove old fittings such as pins screws rivets etc.
Make sure there is no dust or heavy particles.
Remove the tile and prepare the wall according to the corresponding instructions above or tile over the existing tile.
Repair or remove unfit plaster.
How to prepare for tiling a wall.
Start by removing any molding switch plates outlet covers and other hardware attached to the area being tiled.
Use either a hand held sander or an electric sander.
Then fill in the cracks and holes present and use sandpaper to fix any uneven areas.
Place a wide drywall knife on the wall at a 45 degree angle.
If existing tiles are beyond repair remove the tile and install a piece of wallboard in its place.
Move the knife in upward downward and sideways directions loosening and removing the surface of the texture from the wall.
Sand the wall with medium grit sandpaper 80 grit to further smooth the texture creating an even surface on which to apply the tile.
Wait for it to dry then use a filler to make it an even surface.
How to prepare painted or textured drywall for tiling however first you should remove any signs of paint not firmly or tightly fixed in place.
Previously painted textured drywall prep.