Experience?....
Experience is the key to successful boating with these things. Your sportster is pretty much like a big jet ski.
For me, I've lived on the water all my life, so it just seems to come naturally but, when your in choppy water or large swells, then you have to know where to position the nose of the boat. Anyone riding in the trough can roll. When you nose in, you can use the throttle to make the kind of push you need to challenge the swell. You can fly over the top or just glide over it.
But, experience on the water (driving by the seat of your pants) is what will see you through...........:cheers: