An easy widgit I made myself to help lift the cover on was 2 broom handles with rounded ends, 2 tennis balls, a drill and a bit of string.
Cut a hole in each tennis ball and ram it down over the rounded end of the broom handle. drill a hole right through the ball and handle then pass string through and tie ends together.
1 pole either side of the caravan under the cover helps lift it over the top with the balls cushioning the inside of the cover to save shoving the handle straight through.
Hope that might help....works for me