If your goal is to hit a jackpot, you’ll need to opt for a game and a casino which allow large bets. If you want to just “feel the game” without spending a lot of money on it, opt for the game with a minimal betting limit, like the Auto Roulette by Ezugi (£0.1 minimum bet).
The final but one of the most important steps is to find the game with the minimum/maximum betting limits that suit your current financial situation and gambling goals.