We all know that we should have a reliable computer, show up on time, pay attention and be willing to make losts of mistakes. But what else can a student do to really make the most of his/her time with a teacher?
Record your Skype sessions and listen them again later. I found it extremely useful.
Apparently, I should also add: proofread your posts before you click "submit." *facepalm*
Reviewing right after the class! It's easy to be exposed to new information, and then forget it. When you review skype notes immediately after the session, it helps you to actually <em>learn</em> it.
Very good question. I'll put in my 2 cents.
Depending on the student's level;
If it's for learning fluency, then having conversation is great.
If it's for building vocabulary, increasing comprehension, then I think exercises on an interesting topic are better suited.