JRTJH hit every nail right on the head!
If you are still planning on using the cover, you need to make sure it's prepped before hoisting it up on the roof.
Lay it down flat on the ground, outside roof facing up.
Now, pull one side over the roof so side is actually inside out laying on the roof.
Now, pull the other side over the roof and the other side already inside out, so now, the second side is inside out.
Now, tuck both ends over inside out sides and top.
Now, fold the cover in 3rds, starting on one side. Fold 1/3 (long way) over.
Now, fold the other side over the side you just folded. It is also 1/3 long way.
What you have now is everything folded up long way 1/3rd of 8 feet (wide).
Now, either start from the "front" of the cover, or start from the rear of the cover and begin rolling it up to the other end. Just remember where you actually ended up. The end of roll will either be the front or back.
Now, you are ready to hoist the cover on the roof.
Depending on how you rolled it, either front to back, or back to front, lay the end on the appropriate end and place the roll in the middle of the roof.
Now, unroll it, either front to back, or back to front.
Once it is unrolled completely, drop both ends over the ends.
What you are now doing is unfolding it from it's reversed position to its normal position.
Once unrolled, front and rear lowered, lower the last side folded and drop it over the side of the trailer. Now, do the same on the other side. All the sides will drop in place.
At the end of the Winter season, you can fold the cover back up again (inside out) on the roof the camper. Simply pull one side up at at time, then the other, then fold both sides to the middle in 1/3rds again and roll up front to back, or back to front. Just remember which way you do it, so you'll know where to place it next year.
I always rolled mine back to front, so I knew to always start from the front. But that was just me.
Just for what it's worth, I don't cover any more. We use the camper too much in the Winter months and removing that beast with frozen ice IS impossible. Replacing it back again in sub-zero weather is a hospital visit waiting to happen.
This was 2 campers ago. Our last 2 trailers simply got too long. Way too much work to put covers on them, especially my current fifth wheel... way too long, way too tall.