Pay with cash
Using cash automatically makes you spend less compared with using plastic. An oft-quoted Dun & Bradstreet study concluded that people spend 12 to 18 percent more when using credit cards instead of cash.
Why? If you’re worried about schlepping back to the ATM to reload your wallet, you will be less tempted to spend more cash than you have on hand. Also, you’ll stick to your shopping list and resist in-store temptations to buy more items than you intended.