Any time you receive any sort of bill that is greater than $5 (so your $10's, $20's, and $50's or higher), put it in a safe place that isn't your bank! If it is in the bank and you have a debit/credit card, you're more likely to swipe your card and use the money up quickly. If it is in your wallet, you're more likely to use it while you're out and about spending money. Having it collect in a safe place outside of your wallet allows it to accumulate without you realizing it. Visit this stash only when you don't have money else where, and you'll impress yourself with how much money is there! It's like a surprise gift for yourself!