Thought I would post this as a PSA because as per usual, traffic in the Tennis Forum will be about 100x normal here for the next two weeks. This is just free advice from me. You can ignore it or whatever, but if you're a newbie to tennis betting ... this should help you not bury yourself.
1. KNOW YOUR SPORTSBOOK'S RULES REGARDING TENNIS
All books are different. Some rule a match as "action" after one set. Some say two sets. Some say the match must be fully complete. You wouldn't bet football or baseball without knowing the rules ... or if you do, get your shit together and know your rules. So many people wind up asking ... did I win that match or do I get my money back when a player retires .... if you don't spend a minute to know the rules, you shouldn't bother betting on a Slam.
If you bet handicaps or totals, know that matches must go the distance at all books for them to be graded as action.
2. CHALK PARLAYS
This is one of the biggest things that your "Slam" tennis bettor tries to hit. Take a bunch of big favorites and parlay them because it's "easy money." Be careful with this plan. First, your "locks" of each round are usually astronomically high priced and offer very little return for your risk. The ones you toss in anywhere from -300 to -1000 because it's a "name" vs. someone you've never heard of. That doesn't mean it's a winner or a loser, it just means you need to do some research before committing yourself.
3. NUMBER OF PLAYS PER DAY
There's an enormous amount of matches per day early in the tournament. It is very easy to bury yourself in the first two days of a Slam if you make too many plays. Pick a number you're comfortable with each day and stick to that number of plays. Don't CHASE losses. Don't WASTE winning picks. Make your picks for the day early and then relax and wait for them to begin. It's hard not to sprinkle action during all the day parts, but you'll probably hate yourself if that is how you choose to bet a Grand Slam.
4. FUTURES
One of the under-used betting options for Slams. Doing a little research on the draws and seeing the paths for players as they potentially advance can pay dividends by the end of the tournament. If you have book with lots of options, you can also find less risky futures like "a player to win his/her quarter", etc. Using futures gives you hedge out options later in the tournament and money making opportunities - make sure you look at these and don't settle just for making daily selections.
5. SPECIALIZE
With both women and men playing, it is very easy to spread yourself thin by trying to play a ton of both sides of the tournament. I see nothing wrong with playing both WTA and ATP matches in a Slam, but don't kid yourself ... it's difficult to try and bet a lot of matches in both. My own experience ... pick one or the other to concentrate on and sprinkle in some plays on the other side. This cuts down the # of matches you have to look at per day and should help you focus.
Good luck!