Drilax 5-1/8 inch Diamond Hole Saw Glass Cutting Ceramic Porcelain Tile Saw Marble Granite Quartz Coated Circular ( Larger Than 5 inch ) Drill Bit Tip Wet Drilling Core Grit Tool 5 1/8 Inches in

Here is how you could use water to keep the tool cool:
a- You can build a mini water dam around the hole with plumbers putty.
b- You can choose to spray water on the drill bit.
c- Or you can use running water to cool the drill bit.
EASY TO USE
Center pilot drill bits are for wood, metal, etc.; Here is how you can keep the drill bit on target:
a- You can make your own guide out of plywood - plastic or even a card board. All you need is to keep the drill bit in place until it makes the initial marks.
b- You can start drilling at an angle, with the edge of the drill bit making a C slot and then getting the drill bit up to vertical.
c- You can manually guide the drill bit with wet sponge.

Tiles;Glass;Fish Tanks;Marble;Granite;Ceramic,Porcelain;Bottles;Stones