The strategy I followed was based on betting 1% of my bankroll on each bet, I think this is the most succesful method.
My second strategy is to hedge new bonus-offers without risk. There are several bookmakers with delicious signup bonuses. What I do is to have all my bank in Betfair and when I see a new bookmaker I try to take their betting bonus. It's simple, just backing for a certain event on the new bookmaker and laying with the same bank in Betfair. With this simple method I have made a lot of money.
The most difficult thing to do is to bet just the 1% of the bank, sometimes you want to bet more, but I don't recommend this otherwise your bank could be over. Don't try to make a lot of money in a few days, take it as if it was a hobby and never bet more than you can afford.
If you consider these recomendations wining money will be much more probable, making "all ins" can be profitable in short term but betting just little portions of your bankroll is the easiest way for success.