It's really easy if you purchase lots of little things using a non-cash form of payment. It's even easier if what you're buying is non-physical, like streaming movies or video games for a tablet/phone. The key is to remove the physicality on one or both ends of the transaction and keep the single transaction cost in 2-digit range or the low 3-digits. And of course, never budget, ever, and try not to mentally track how many purchases you've made over the past few weeks. Do that as a pattern, give it some time, and money will evaporate Brewster's Millions style.