The best way to win more games on roulette (or to minimize the risk to lose money on the roulette wheel, if you wish) is to focus on the outside bets. Although these roulette bets do not lead to mind-blowing wins, keeping your bets on the odds/even, red/black, and high/low gives you the highest chances to score a win.
Find a roulette table with a high max bet and a small minimum. Bet a small amount on black or red; even or odd; or 1-18 or 19-36. Keep your wager on the same spot on the table until you hit it. If you keep losing, keep betting a very small amount.