Prime to seal it and let dry.
Mudding a wall before tiling.
As for mudding to make it even i would not even attempt it.
Start with planning your wall tile installation.
How to make a plaster wall level before adding tiles.
Even walls covered in drywall.
Prime the surface prior to the tiling.
If the drywall dust is not removed before applying the primer the primer will not stick to the wall.
If existing tiles are beyond repair remove the tile and install a piece of wallboard in its place.
I would redo the wall yes more work and a delay but it is not a patch it will be right when you finish it and all those other issues you bring up will also be addressed in one instance.
Do a precise measurement of the surface.
Wash the wall with tsp tri sodium phosphate or an ammonia based cleaner to remove any grease or oil.
The technique of layering means for you to apply one layer of filler and let it dry before you apply the next coat.
Plywood or drywall is insufficient as a subfloor because it is a permeable material that will rot away when exposed to water.
Use even pressure and do not force the primer onto the.
Vacuum clean and wipe the walls.
Count how many tiles you ll need.
How to use mud on uneven drywall.
Cement backer board a type of wall.
Drywall is smooth flat and easy to install.
If it was just a small spot ok.
The definition of level is expertly argued on points that range from the shape of earth to the surface s relation to the plane of the seas.
Remove the tile and prepare the wall according to the corresponding instructions above or tile over the existing tile.
To do so make sure all of the tiles are intact and secure.
You may also paint this area if only tiling a portion of the wall to minimize cut in work around the tile.
Application roll on the primer the same way you paint a wall.
Repair any loose or cracked tiles.
Poor adhesion causes texture to peel and bubble from the wall and create an unprofessional looking texture and plaster finish.
Sand the area with medium grit sandpaper until even and vacuum up the dust.