Granite sinks and granite composite sinks will typically come pre-cut for faucet holes. Since a homeowner may use several combinations of faucets, soap dispensers and pull-out sprays, these holes are usually left intact and covered. Before the sink is installed, you can knock out the desired number of holes, in the positions that will best fit with your faucets. Most sink manufacturers will clearly mark the holes on the front of the sink. If the holes are not marked on the front, turn the sink over and look for a groove cut into the stone surrounding each cutout from the back.
Position the sink so that it is comfortable for you to work with. Rest the sink on a flat, horizontal surface, with the top of the sink facing up, or rest the sink vertically against your legs, with the top of the sink facing out. Locate the sink holes you would like to remove. These will either be marked on the front with a coloured sticker, or on the back with a groove around each hole.
Place the tip of the metal punch in the centre of each hole to remove and hit the end with a hammer. This will punch out the hole. If any large pieces remain, hit them gently off with the hammer.
File down any jagged edges by placing the file into the hole and working it both up and down, and side to side around the hole until it is large enough to hold the faucet.