The following is only what I've read; it does not come from personal experience, so take it with a box of salt:
I have 27 eggs for my doctor's wife that will be going into paper mache egg cartons tomorrow, Tuesday, for the final three days. I have cut a small hole in the bottom of each egg section for air flow around the eggs. I will put the eggs in with the large end at the top. Supposedly this gives the chick inside two-three days to get into position to begin pecking its way out, causing the top half of the egg to break away. Meanwhile, with my humidity's being between 60%-70%, theoretically any excess moisture will go to the bottom of the egg, saving the chick from drowning when it first pecks into the air space at the top of the egg.
Supposedly, using this method keeps the hatched chicks less exposed to cracked egg shells, and it makes it easier to clean the incubator once the chicks are removed. Guess I'll know for sure Thursday.
The alternative is to lay the eggs on their side on the floor of the incubator, slightly tilted with large end up. This supposedly will produce a hatch similar to what happens when the eggs are under a hen. I've done that, and it worked, messy, but it worked.