Drilling a 10mm hole in tiles

Working on a kitchen reno I have to mount power points on tiles.
Normally the tiler leaves a big enough hole for me to put a bracket in behind to screw the thing to
But this tiler hasn't so Monday I will have to drill directly into the tile

Any advise on doing it without cracking the tile.

I'm told the diamond shape glass/ceramic (spade type) Bits are the best to use.
What about using water as a cooling agent (is it necessary)

A while ago I was given a task to mount on to granite and was given (on loan) this sort of thing http://www.sutton.com.au/uploads/dow...hurelowres.pdf
But the home owner changes his mine (as they all do)

Any thought on these bits


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