It's highly recommended betting in the “pass line” and not in the “not pass line”. That's because betting the pass line leaves better probabilities and money.
In your free bets, take as many odd Bets as possible. These bets are the ones that leave less winning percentage to the bank. Remember: the more free bets to the odds in proportion to the pass line, the lower the percentage will be for the bank!
To make your game more agressive, bet more than one point each hand.
Put your bets in the pass line and the come bet, and also the odd bet, as was said before. Don't take the rest of the offered bet on the table, those are for unexperienced players and they usually pay horribly.