I didn't do the envelope system but I did do a careful budget. I took my two smallest paychecks of the year and based my budget on those. Then I'd subtract all my fixed costs - mortgage, insurance, phone, cable, etc. - based on the highest bill I'd paid the previous year. The money I had left over, I rounded down to the nearest $100. Then every day, I wrote down what I spent, rounded to the nearest $1. That coffee I grabbed on the way to work? I'd get a receipt and write it down. Whatever it was. I bought almost everything on my credit card so I'd automatically get the receipt and then paid the card off every month. Plus, I got rewards points.
The first thing I did was stop buying coffee. That was $10-15 a week I really didn't need to spend.
Then, the two months of the year where I'd have a third paycheck, that money went into savings or towards the purchase of something big that I needed. And after about July, the deductions were reduced because I'd maxed out a lot of them. That extra money went towards Christmas spending and savings.
I did so well with it that I don't even bother to track any more.
My list of things you need to know:
How to drive
How to do basic stuff on your car - check the oil, add windshield washer fluid, change a tire or at least have auto club, know the maintenance schedule for your car to take it in and get it done, know how much oil should be in there, how to check other fluids
How to do laundry properly
How to clean properly
How to budget
How to cook at least basic things
How to do basic household things or at least how to recognize when you need to call someone.
Know how credit works - if I need money that I can't pay back right away, how do I get the lowest interest? Hint: It's not payday loans LOL
I like some of the more esoteric suggestions, like how to fight fair, too, but this is my basic list.