Cover rain gutter extensions with tennis balls with an "x" cut into them. Pool noodles and pipe wrap can be used to cover other sticky outey bits.
Give the outside a good cleaning before storage.
A good coat of wax after a thorough cleaning will also help.
Some just hoof the cover over their shoulder and haul it up the ladder, some climb the ladder and haul it up with a rope.
Unroll the cover down the length of the trailer and then drape over the sides. Attach buckles and straps as applicable to your cover.
Fold it up in the reverse order of installation (lift up sides, fold and roll down the center) so that it goes back on easily after removal.
Your best bet to install it without trouble is when there's low or no wind. Early evening and first thing in the morning are typically lower wind times.
Keep it tight to prevent wind rub.
Brands are what brands are. Get something that "breathes" to help keep moisture down. Longer warranty implies better quality, but is not always the case.
I've for a Camco Ultraguard on order and should be lifting it up tomorrow.
That's about all I've got to offer ya.