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.
Outside bets in roulette carry the lowest risk. They cover more numbers yet the payouts are lower (1/1 for Red, Black, Odd, Even, 1 18, 19 36). These outside bets carry the best prospects for long-term wins.