Hi there,
This is a good question and we get this one a lot. But you should move onto the next lesson after you feel comfortable enough with following along with what the instructor is teaching. We do not expect you to completely memorize every exercise by heart.
Also, if you curious about the next lesson, or bored or stuck with the lesson you're currently on, it's a good idea to get a refresher and move on.
It's important to remember to have fun.
I hope that helps!
If you have any questions, comments, or concerns, please contact us.