Otherwise the best idea is just to brainstorm as many questions as possible that examiners could ask you about and prepare answers for each, that's essentially what I did.
Definitely recommended. I remember both my Chinese school teacher and day school teacher giving me a list of "highly probable" questions for SL. If you answer the questions fully, commit the answers to memory and also (most importantly) add in some extra questions that you think the assessors will ask because of the answers you give, then I'd say you're pretty much set for the oral exams.
For example, back then, one of my future aspirations was to be an aerospace engineer. I thought that the assessors will ask, "Why do I want to be an aerospace engineer?" and "What are the pros and cons of being an aerospace engineer?" So I prepared for those questions and thankfully, I reaped the rewards.
