We use a piece of strapping the same as seat belt strapping that goes over the barrel between where the awning starts and the arm starts. Then we use some small d-shackles to attach a guy rope and peg into the ground. If the wind dictates, we will also attach the de-flappers if needed. Legs up or Legs down, again dependant on wind and how we are setup. We quite often have two vans with their doors facing each other, far enough away to roll each awning out.
I would post a pic but i haven't got one. I can get one in a week or so if you like?
Cheers
Ants