When you load the game, you will see the familiar game area on the right side of the center. On the left is the payment form, which shows the various rewards that can be used to make different combinations. On the right is the information panel where you can view your bets and any bonuses.
The goal of Cash Blox is to complete the entire line of the game area - you don't have any input, it's done automatically by the machine. The basic victory is a complete line, but more valuable are doubles, triples and quads. When a line is completed, it will disappear and more blocks will fall from the top to replace them; a more complete line can be formed in this way.