Just leave them be. As long as humidity is OK, they shouldn't need help. Some will start and then not do anything for a LOOOONG time. I only help if they have been at it for 48 hours or more and look like they are not going to get any farther. I have hatched quite a few and they will surprise you. The ones you think are never going to make it because they aren't doing ANYTHING will suddenly go to town and hatch out so fast you'll miss it. Just like any animal in labor, some babies come easily and some take hours or days to come out and greet the world.
I know it's been said before and I know it's very hard to do but HAVE PATIENCE. You will have fluffy butts before Easter.