You can either use a hole saw or a chisel to widen your drilled hole or you can do it manually with a hammer. Hole saws are great for when the drill bit is too big in diameter, but if you’re going at it by hand, then make sure not to put all of your weight behind the object because this will just make the object split and break after a lot of pressure is exerted. This usually works best if you feel like your drill bit isn’t big enough for the type of hole that you have to go through, but in some cases, this might not be possible because it can cause an accident with how much force is behind it.