What's the best way to do it?
LISTEN to your partner. Don't just wait for your turn to speak. Be interested in what they are saying and politely agree or disagree. If you disagree, try to persuade them to change their idea, but don't spend too long doing that.
Refer back to things you already said.
Say a couple of sentences then ask a question. Never answer your own questions!
Try to look at your speaking partner more than the paper.
Some students turn their chair a little bit - towards the other student. This helps them to remember who they should talk to.