Jonathan Atkinson is right. Instructional videos can be very helpful—you can watch a figure be danced correctly 100 times in a row, if you need to. But a video can't tell you "You're not doing that quite right; do B instead of A."
When I was first learning to dance, often I could pick up a new figure and do it reasonably well during the lesson, but far too often I couldn't remember it the next day. So I started writing everything down right away. I have several thick notebooks with the details of dance patterns. That's where a video can be really helpful, taking the place of notes (which may not be quite right, anyway).