In college basketball and college football, do a parlay of multiple games of heavily favored teams (-300 or lower) playing at home using the moneyline. Even if you have 4-5 games you will likely only double your money (and you will get burned occasionally) but this is an easy way to double your wager frequently. I hit an 8-game NCAAM parlay last night and none of the games were particularly close but I only made about +130 because they were all really heavy favorites.

In Major League Baseball, find two or three 'aces' starting at home. They win the vast majority of the time so the moneyline is usually safe to parlay. If other circumstances (opposing pitcher, etc) align properly, you can even parlay the spread on those games and the payout will be much higher.

For NFL and NBA I focus more on individual player prop bets. For instance, taking Davonte Adams to have 7+ receptions or 85+ yards was like stealing this year.

For PGA, I generally look for a 'horse for the course' and take him to finish top 10 or top 20. The odds for those are pretty good. For the Pebble Beach tournament this week you have several guys (Day, Mickelson, Streelman, Casey) who have long and successful histories at Pebble Beach. I picked a few of them to finish top 10 or top 20 and I should net a profit unless they all play like I do.

Good luck - you already got the tough part right ... "I don't intend to bet any money that I can't afford to lose". I do it strictly to make sports more entertaining.