In order to make the unit system profitable in sports betting you have to think like a professional gambler. Whereas the amateur bets with whatever he has in his pocket at the time, the professional sports bettor will divide his bankroll into smaller easier to handle amounts. With these smaller wagers, he has less chance of being wiped out and losing his whole bankroll. Having fixed units makes the keeping of records much easier as well. As a gambler, you should know the state of your bankroll.
If you pay for betting tips, then there's a good chance you're a mug, and will receive nothing of value. All tipsters are scamming gullible gamblers. If you had a fool-proof way of picking winners, would you share those profit making tips for just a few dollars? These tipsters prey on desperate gamblers and those with no understanding of how betting works. In a way they are paying someone to make the bets for them. Even if you were to win, the fee for the tip would swallow any possible profit.
One of the reasons that we all love watching sports and supporting our team is an emotional one. But if you're taking a punt on the game, you should never let your emotions come into the equation. Likewise, blindly supporting your favorite team is a sure-fire means of losing money. As a sports bettor, you should be on the look-out for "value". After all, your job is to make money. That will often mean betting against the favorite. Another important point is to take care of your bankroll.