gazs,
Join Airservices, become a controller, clock up five years experience and then, if you're the travelling type, leave. You need a minimum of five years experience to apply for jobs overseas and if you have the courage enough to take that step and take your chances in the international world of Air Traffic Control, the rewards will far out-weigh any small sacrifices you might find that you make along the way. You'll gain skills in ATC and knowledge in aviation that you won't find in Australia and see parts of the world that you might never have seen if you choose the long career in Airservices and do nothing but watch football on weekends and holiday in-country. If you stay in Australia, don't stay in one group or position longer than five years, transfer to another position or group if you can.
Training sucks in ATC, but if you keep plugging away at learning the job, you'll find it easier with time. Study hard, maintain your confidence in yourself (without being over-confident!), be honest with yourself and your instructor and heed the advice that the boys have given above.
Join the union, Civilair, but don't expect too much from them. They mean well, but tend to believe that they know what is in your best interests in any given situation, more-so than yourself, and they will threaten to remove representation if you don't agree. Unfortunately, sometimes they are wrong.
Trust your instincts and definitely keep a low profile. Intellect and independent thought is viewed by many as a threat (for the life of me I don't understand why, but it's true)... unless you're in the "club".
Don't talk to your Operations Manager other than to smile and say "Good Morning". If your Operations Manager invites you into his office with a smile and closes the door behind you, get up and open the door and walk out of it. No, you don't need his/her permission to leave the office. Just make sure that you're never in it alone, informally or formally. Get everything in writing and keep a diary of every that is said to you by your Managers and your Supervisors with times, places and dates, it's worth gold when you need it down the track.
Ozzie ATCO & En-Rooter are 100% correct. But, if your heart is set on becoming an Air Traffic Controller... don't walk away.