Wait for the balls to hit the collect for your money to increase. Upgrade you multiplier to get money faster. Multiplying rule: $20 = +1 Multiplier (It will automatically buy large amounts of the multiplier if you have enough) Press the "New Background" button for a new background, click it more for different backgrounds.
If the balls stop spawning, you might have to click the green flag to get then to start spawning again. (Yes, this will reset your progress, so hopefully this won't happen to you.) This is a new game I made to compensate being gone for so long, so sorry if it's very buggy! (Like many of my other games-)