EVERYTHING. Every card swipe, every cash transaction... everything. And tally it.
By the end of a week, you should have a pretty fair idea of all your money "leaks", and can then determine which things you no longer want to waste money on... if you've kept up with it and can still find the notebook! I never can.
I've had sole control over one of the joint accounts for a few months, mainly because I'm treating it like my little savings piggy bank. I'm putting half my "side money" away for a special treat (electric assist for my trike), and half to pay down our credit card at that same bank. But because I never carry a checkbook with me when I make my deposits (or rare small purchases), I often forget to write the transaction in the register when I get home. It's not like I ever write checks, anyway, so I was grumbling to myself that there should be a debit-card, wallet-sized register that I could carry with me, so I'd know my balance at all times.
Yeah, I know, there's probably an app for that. I'm still trying to learn how to use Evernote, lay off. ;)
I searched online, and there are a lot of preprinted registers that you can order - not very expensive, really, but sort of a pain to order and then have to re-order when you used them up.
You get 8 pages of compact note taking ability that fits in your wallet or pocket, and when you're done you can recycle the paper and print a fresh one - no need to order one, pay for it, wait around, know that you're contributing to the fall of Western civilization by wasting money, time and fossil fuels for the "convenience" of having someone else print out a register for you!!! (Pant.. pant... calming down now.) And best of all, it's so customize-able. There are even reference pages you can put in, like Morse code, tip calculators, conversion references, and a Simplified Dvorak Keyboard printout, should you be so radical as to want to learn to type a whole new way.
I printed two, one for each account, and I'm going to TRY to keep both updated so I don't have to wonder what the balance is - I can just look. I'll still have to check with the hubby before I spend anything major, since the notepad can't tell me when the bills arrive... UNLESS I MAKE ONE where I write down what day the major bills are due and the usual amounts they are!!!
Off to print some more! :)