There has been enough good advice to fill a book, so I'll attempt to keep this brief.
If you have the option, consider flying overwater with the doors off. It will make it easier to get out if the unthinkable happens. In 1997 I was the first on scene to a USN OH-58C that rolled over on takeoff (it was on floats) into the Patuxent River. The airframe deformed to a point where they couldn't jettison the doors. Fortunately they made it out through the windshield area (the windshields were gone). It was an awfully long 20-30 seconds between the time they rolled over and when I saw the crew emerge on the surface.
From my days in the Navy, I seem to recall we always flew the 206 from the deck with the doors off.