The buy signs show you what keys to press to buy them. You are not supposed to constantly be in the positive, just don't be in the negative and be really high in the positive before the final milk timer runs out. Also, You're supposed to get to the win screen before the song ends, so ready your fingers! Final note: completing means, you buy all the stuff, in the end you're in positive money numbers, and you blasted you fingers on the final milk countdown. My high score is 12,000. Try and beat me!
Credits to google for the music!
