Disclaimer: This is a noobish question, so please be gentle...then rough

I'll be completing my lessons over the next couple of weeks and I would prefer to have my own basic kit setup (wetsuit, booties, gloves etc) and not have to hire, so I can be comfortable and be able to learn in the gear I'll be using.
I have a 5/7mm semi-dry I use for diving, but I was hoping someone could recommend or point me in the right direction in regards to choosing the best brand/style wetsuit for kitesurfing (in Sydney climate).
Am I able to use my current wetty for both diving and kitesurfing? I'm assuming it's best to have seperate gear for each due to differences in requirements and wear etc. Any info will help.
Cheers