Get brand new rock hard good quality drills, a greater quantity of the smaller diameters. As said drill a small pilot hole (another reason for buying more) Use a good centre punch to mark hole. Start the forst hole dry, no cutting compound, when you are through use the cutting compound on the larger diameters. Go slowly and watch out for the drill (if hand held) snatching, so dont hold your thumb over the handle keep your thumb on same side as fingers. Dont forget to pick up the swarf or it stick into things and stay there and rust - stainless does rust believe me!
As you might imagine I used to drill lots of holes in stainless in my former life.
New boat is here, very happy!