Measure and mark the precise area where you want to drill. It is a good idea to measure and mark the area twice.
Measure and mark the center of the hole. This is where you will place the center part of the hole saw.
Equip the drill with the right sized hole saw bit. The hole bit will be the same size as the hole you need.
Put on safety glasses. Center the hole saw. The center of the hole saw bit protrudes and will drill the pilot hole before making the actual hole. Drill with the hole saw bit slowly, applying gentle pressure. If you drill too fast or push too hard, you may chip or ruin the Corian countertop. Do not drill at a slant or the hole will slant.