Jack and I have been working on this trick for awhile. I started by allowing him to roll after each ride. Then I asked him to walk with his nose to the ground while on the lead rope. That lead to him rolling while on the lead rope. I needed him to be comfortable with me beside him while he went down. Once this was consistant I then allowed him to lay down to roll but gave him a treat before he started the roll. He then understood I just wanted him to lay down. Before I attempted to sit on him, I made sure he was relaxed with me beside him laying down. This took a day or two. The film is the second time I mounted him while he was laying down. He was a rock star and I had a blast teaching him this new trick.