The 'Pivot' system is based on the 'Law of unequal distribution' and is a good system. Numbers on a roulette wheel tend to repeat often. On average, only 24 different numbers will appear in 36 spins of the wheel. Rarely, if ever, will all 36 numbers appear in 36 spins.
You start by taking a scorecard or a pad and write down the winning number of each spin until one number repeats. The repeat number is your 'Pivot' number and you place your first bet on it, straight up.
Example: suppose numbers 6, 17, 8, 22, 16, 21, 34, 12, 15, 8 come up. Number 8 is the first repeat number and therefore the 'Pivot' number. Number 8 will remain the 'Pivot' number for the next 36 spins in a row unless you win.
Bet the same amount, say one chip, on your 'Pivot' number for each spin until you either win at some stage or lose all 36 spins. A win on a single number at roulette pays 35:1, so if your 'Pivot' number comes up anytime throughout the 36 spins you will be a winner or break even if it comes up on the last spin. Obviously, the earlier your 'Pivot' number comes up the better the profits because your profit decreases with every spin of the wheel.
When you have a win, stop betting on that 'Pivot' number and select another one to start the process all over again.