Roulette Tips Video Source & Information:

This modified martingale system can be used on the columns or the dozens bets. We are going to use the last roll to our advantage. The last roll was a 14 so we are going to place two equal bets, one on the first dozen and one on the last dozen. You have a 63.2% chance of winning, and if you win you will start over and place the original bet amount on two dozens again, only this time you will skip the dozen that was last landed on. This is done because the odds are in favor of the ball not landing in the same dozen twice in a row.
Continue this strategy until you lose, and you will lose eventually. If you’ve
been switching the dozens around with each bet then keep your bets in the same locations. You are going to triple each of your bets. In order for you to lose this next bet the ball would have had to land in the same dozen 3 times in a row and the odds of that happening are about 14 percent. Those are pretty amazing odds. This strategy is a blast because the chips stack up quick and you’re always moving your chips around. In the off chance that you lose, go have a drink, come back later, and try again. This is one of the best ways to increase your bankroll so enjoy it and good luck at the tables.

Source: YouTube