Answer: lay the tiles on a wooden floor and use a drill with earthenware drills, drilling at a progressive speed.
You can also drill tiles before and after laying them, but it is preferable to do it before to avoid any problems. However, you must use the correct material to avoid damaging the tiles, or worse still to cause them to burst. You must use a drill that allows you to control its speed on the one hand, and drills suitable for earthenware on the other hand. The earthenware drills are the only ones that can drill tiles safely, there are any diameter. Before drilling, lay the tile on a wooden board that will absorb the vibrations of the drill. Drill slowly at first, and increase the speed gradually after starting the enamel. If you follow all of these guidelines, everything should be fine. You too, send us your brico question