On test book page 113, it says to complete two patterns of waltz eight on each foot. Then it says this move may start on either foot.
I think it means to do the pattern twice without stopping, starting on the same foot (your choice which one) each time. But isn't the wording weird?
I thought this means you either do {left then right} or {right then left}
You do the entire figure 8 twice. You may start on either the right or left foot; most people (in my area) start on the right. You don't stop between finishing the first figure 8 and starting the next--you just change feet and push and continue on.
Yep, what everyone else said. I normally start with my left foot since it's my stronger side, then do the right side, and repeat the left and right again, there's no stop. You could start with your right foot, but you still complete the pattern twice before stopping.