I am an accountant, so a lot of this is what I do for living.
You are all correct
buy extra food when you have money
get rid of all of your credit cards except one
Freeze it in a block of ice in the freezer
Remember getting an allowance when you were a kid?
Get an allowance, When it is gone - too bad
Plus a very important one
set up a bank account that you cannot use online or a bank machine.
Every week put a set amount in it. no missing weeks
Don't even think about this money
It is your " holy crap I need new brakes" (whatever) and now I have put aside to help with that