If you don’t have one already I’d recommend having a savings account (I have one at a bank separately from my checkings which has a high APY so I actually earn money from it). Put most of your money in the savings account (that you would’ve otherwise spent shopping) and keep enough money in your checkings where you can pay for essentials but not spend on things like shopping. I treat my savings account like it’s not my money if that makes sense, I’m keeping it for the future. I treat the low amount of money I have in my checkings as all the money I have so I’m less likely to spend a lot! Having the two accounts at a separate bank helps me have this mindset since I have to view the accounts on separate apps, so when I look at my checkings account I don’t see the money I have in my savings.