In wrapping the polo wraps, you line the Velcro up and roll it that way.
When you wrap the leg, you start at the top of the leg, below the knee. You want to wrap to the outside and bring the roll up between the horses legs. So you start at the front of the leg, wrap it back towards you, roll it between the legs and continue. This pulls the tendon to the inside. You never want to pull the tendons to the outside. That's how you injur the horse. After you wrap once, you pull it snug and go for another round. Pull snug, wrap again.
You travel down the cannon bone until you hit the fetlock. Wrap 3 times around the fetlock and rewrap going back up the horses leg.
Not the best pic, but you can see the polo wrap on the rear left leg, how it goes from back to front through the Inside of the horses leg. My instructor told me that imagine the roll was a fish, and it was swimming up stream through the horses leg and towards its head.
Anyways, I will try to find you a video. Polo wraps take practice but I love them over boots.