Easy money
Play Sit & Go at the maximum allowable entry fee with two players, no limit, and the game of your choice at the novice level. Go all in as soon as you have even a marginal hand. Your opponent will do the same if you go in with only your dealt cards. If you win, save the game and play again at the maximum allowable entry fee. If you lose, turn off the system. You will have not lost any money and can try again.
Never lose
When you sit at a table and the cards are dealt, save the game before betting. You can then move all in or bet the maximum amount. If you lose the hand, just exit out of the game, and load your saved game. When you are back at the table, you will have the same cards as before, and the outcome will be the exactly same as it was when you lost. Simply fold instead of betting. Also, if you save the game and decide to fold but realize you would have had a really good hand, just reload the game and play the hand. The outcome will be the exactly the same again.