Sealing your shower walls is essential for tiling the surface to prevent moisture from effecting the integrity of your tile installation.
Mudding a wall before tiling.
Poor adhesion causes texture to peel and bubble from the wall and create an unprofessional looking texture and plaster finish.
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.
How to make a plaster wall level before adding tiles.
Drywall sheets are a big improvement over plaster and lath type walls in older homes.
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.
Application roll on the primer the same way you paint a wall.
If it was just a small spot ok.
Use even pressure and do not force the primer onto the.
Cement backer board a type of wall.
Prime to seal it and let dry.
Drywall is smooth flat and easy to install.
Plywood or drywall is insufficient as a subfloor because it is a permeable material that will rot away when exposed to water.
Even walls covered in drywall.
Sand the area with medium grit sandpaper until even and vacuum up the dust.
How to use mud on uneven drywall.
Remove the tile and prepare the wall according to the corresponding instructions above or tile over the existing tile.
If existing tiles are beyond repair remove the tile and install a piece of wallboard in its place.
As for mudding to make it even i would not even attempt it.
To do so make sure all of the tiles are intact and secure.
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.
Start with planning your wall tile installation.
Vacuum clean and wipe the walls.
You may also paint this area if only tiling a portion of the wall to minimize cut in work around the tile.
Wipe with a damp cloth to remove any remaining dust and allow to dry.
The technique of layering means for you to apply one layer of filler and let it dry before you apply the next coat.
Repair any loose or cracked tiles.