You upgrade your Lemonade and lemonade cups to make more money. The amount used per customer improves along with your Lemonade, though refilling it gets twice as expensive. Its randomized so you always have a chance at getting 1 dollar but it can be more, and more gets a lot more likely as you upgrade. V.I.P.s pay more. Hit upgrades to see your upgrading options (Upgrade is the button). If you want to upgrade you have to have enough money afterwards to re-fill. That way you won't soft-lock.
I want to thank TrashGames_ because looking at his game code helped me understand how to randomize.
