MudRunner

This can be easily achieved in the "Climb the Hill" Challenge.
Crawl up the hill by following the on-screen instructions. Up there, just keep the left side of your Jeep on the road, whilst the right side is going slowly down the hill (adjust steering if necessary, but crashing shouldn't be too hard ). When falling down, you most probably will roll over your roof.

Easy squeezey achievement.
Boot up the "Climb a Hill" challenge (have to complete the first two challenges, first), and crash off the side of the hill, you will more than likely roll over the edge of the trail, so you'll probably get it the first time you do the challenge