When you arrive to the table, locate the placard that shows minimum and maximum bets. You'll need to hand your chips to the dealer so they can give you a specific color this way, everyone can keep track of their own chips on the roulette table.
Atmospheric conditions continually change and the wheel itself has features that encourage randomness such as the size of the frets between the numbers and the diamond-shaped obstacles that intercept the ball as it falls down to the wheel. This means that you cannot predict the exact number where the ball will land.