To drill a hole in a ceramic tiled wall, whether in a kitchen or a bathroom is not only difficult, but presents some disadvantages as well.
The most important is the potential infiltration of humidity, which can accumulate behind the tiles and eventually cause them to become loose.
Before drilling ask yourself if it is absolutely necessary to drill.
If it is unavoidable, drill preferably in the joints between the tiles rather than in the tiles to avoid splitting or shattering them.
The diameter of the hole should not be larger than twice the width of the joint.
You can in that case drill several holes.
If you must drill into the tiles you can use two strips of masking tape placed in a cross over the tile and drill in the middle of it.
Before drilling, mark the spot when you need to attach your hook or screw.
Choose a drill bit corresponding to the size of the rawl plug you intend to use.
It is better to use a drill with an electronic variable speed which will adapt automatically to the work you are doing.
Choose also a tungsten drill bit.
If your drill is not equipped with an electronic variable speed, start by going very slow in order not to break the tile.
Increase speed as you feel the bit going into the tile.
Finally go to full speed to reach the maximum depth of the hole.
Choose your hardware (rawl plugs, screws, hooks) in function of the materials behind the tiles.
One last tip: If you intend to plug a hole in a ceramic tile, you should use a tinted cement that will blend into the color of the tile motif.
To repair a hole in the joint between tile, sand the joint down and replace it with new grout.