tips and tricks?

i’m 18 years old and live in america where u need to be 21 to drink, i found a shop and got cool with the owners and they sell to me no questions asked, so i can sip whenever i want, however it definitely has gotten out of control, as in a 12 pack a night, what outside of simply refusing myself the beverage can i do or what have ya found success in limiting what u drink? any tips or tricks are appreciated, na zdrowie friends!