To cast the Dice and move your Token around the Board, simply tap the big red "GO!" button!
Each tap will use up some Dice Rolls, depending on your current Roll Multiplier.
 
Also, once you reach a certain Net Worth, you'll unlock Auto Roll!
 
Once unlocked, activate it by holding down the "GO!" button until it turns green. During Auto Roll, your Dice will be automatically rolled, even after Bank Heists and Shut Downs!
 
To stop Auto Roll, simply tap the "GO!" button again or any other menu item.