Here's my tips for starting:
* Start with a certain amount in your "bank", and be comfortable with the fact you could lose it all
* Bet 2-5% of your bank on each bet. Don't go increasing the %s if you start winning, or increasing them to chase losses. 2-5% will mean you stay in the game for longer when you get on a bad streak, and that happens to everyone.
* Spread your money around multiple bookmakers, and use the sportspunter.com odds comparison service. Bet with the best odds each time, and bet with the best line each time. This is crucial to increasing your profits, you can turn a losing bet into a winning bet simply by choosing a boomaker that gives your team, eg 7.5 start instead of 6.5 start.
* Know the maths. Work out the percentages using the formula 100/odds. If the odds are $2, the chances of a team winning are 100/2 = 50%. If the odds are $1.50, the chances of a team winning are 100/1.5 = 66.67%. Work out your own %s before you look at the odds. When your %s are greater than the %s of the odds, that's when you bet. It doesn't matter if you think a bet will win or lose, go by the %s, and if your %s are right you'll make a profit. eg if you think a team is a 20% chance of winning ($5 odds), and you can get $6 odds, then take the $6 odds even though you don't think they will win.
cheers