Stop buying things you don't need, especially if you're putting the purchases on a high-interest credit card. Before you buy, ask yourself the following: "Is this something I really need?" "Do I have something similar already?" "Do I want this more than I want to become a millionaire?" Every dollar you spend on something you don't need is one less dollar you can invest. Here's a reality check: If you invest an extra $25 a week for 40 years, you will end up with an additional $277,693. Can you cut $25 of unnecessary spending out of your weekly budget?