IMO, don't do anything. You don't need to know about about shooting a gun prior to them teaching you. You are a clean slate with no bad habits to undo. I went into the military with no experience in weapons whatsoever and became very proficient because I paid attention to my instructors. Listen to what the instructors tell you instead of the bad advice you may get from the no-it-alls around you in the academy class.
"We enjoy freedom and the rule of law on which it depends, not because we deserve it, but because others before us put their lives on the line to defend it."
- Thomas Sowell