Measure to find the location for the hole. Tear off several pieces of duct tape and attach them to mark the location for the hole. Arrange the tape from top to bottom so that the pieces overlap slightly at the edges.
Measure again and mark your planned hole on the duct tape with a permanent marker. Attach a diamond-tipped hole blade to your drill. These blades are available in a variety of sizes, so find the one that matches the hole you need to make.
Place the hole blade over the marked cut. Ensure the edges are aligned with the edges of the planned cut, and that the centers are lined up as well. Turn the drill on a low speed.
Press firmly on the drill. Ensure you use even pressure across the entire hole blade. Maintain consistent force until the blade cuts completely through the granite.
Turn off the drill and lift the blade out of the hole. Make other necessary cuts in the same way as you did the first. Remove the duct tape strips and clean the granite with a rag dipped in adhesive remover.