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.
Sports betting is very different from casino games in one very important factor, namely, there's no fixed house edge, whereby the casino can take a fixed percentage right off the top of every bet. To that end, if you want to be successful at sports betting, you'll need more than just plain luck. You'll need some skills. So in some ways, you could almost compare it with poker or blackjack at the casino.