The "rounder" end is where the airsac is and will need to be up. The turner tilts it 30 degrees both ways.
As a newbie, the most helpful word of advice I can give you is to use the "search" button located in the blue bar. If mine could be worn out it would have been gone the first week! Also, at the very, very top is the "Learning Center"- there is a place there on incubation and other topics that you will find useful.
Welcome to our addiction, and hope you have a great hatch!