Tanny,
Of course I always try to run out a fast UPD, but sometimes that doesn’t work out. When I end up rolling, I usually start with the miracle of getting one foot on the ground and then tipping forward, getting a hand on the ground, tucking in my head and going ass over tea kettle. Not exactly graceful or painless. There are plenty of videos on youtube that demonstrate rolls in various marshal arts. It’s the same idea but with a higher and faster start. The only practice I’ve had has been real life crashing. I’ve never even tumbled on the grass for fun. I think the key part is to instinctively tuck in your head. Otherwise you’ll end up with your face, chest, abdomen and knees scraping across the pavement.
As SinisterJay points out, one of the great things about unicycling is that the uni doesn’t tangle you up. It’s history behind you.
Geoff