Most important thing to remember about soccer betting or any type of betting is to treat it as a form of entertainment expenditure and not as a potential investment or a means of making money. When u place the bet, treat the money as if it is gone and not as if you will get back x number of times back.
The second thing is to bet what u can afford to lose, which is also a subset of the first point.
Now for my personal soccer betting ideas. :o
1. Always bet small, $5 or maximum $10. last world cup, saw a guy place $100 bet on Mexico to beat South Africa in the opening game. Odds were only about 2+, result was a draw..............
2. Bet only on fairly high odds, never when odds are less than 5. Ok, chances of winning are small, but if u only win one, u cover almost all your bets and perhaps more. Bet on small odds could still lose since football very unpredictable and if u win, it's nothing. Hence, usually total goals, exact score, underdog, etc.
3. Bet only on games u have interest in or are watching, to make them more exciting. Hence s league, serie A, friendlies, asian teams, j league, k league, usa league all out for me. Remember, betting is for entertainment and to make the games more interesting, not to make money. You will be very sad if the latter is your objective. :o