Inspect the frame at eye level, hanging it vertically above the hive box.  Make sure the frame stays vertical, so nothing falls out of the cells, such as uncured honey or larvae!  Holding the frame above the box ensures that if a bee falls off the frame, it will fall back down into the hive box and not on the ground.  This is obviously critical for the queen.  Dropping the queen on the ground is generally a very bad thing.  If you don't know she's there, you may either step on and kill her, or she will be unable to crawl or fly back into the hive.

Detailed Instructions: Inspecting the Frames