Write out a good, honest budget. Very few people even know how to do this. Consider all of your expenses for the entire year (including holidays, travel, auto work, etc.) and divide it by 12. It's generally very eye-opening just how far over your monthly income that number is. Now start going line by line, and make a very specific plan on how you're going to cut that down, and create a new budget based on those resolutions. Use the envelope system until you get used to living within your means, it works very well -- once there is no more money in the envelope, there is nothing to spend for that part of the budget unless you want to take it from something else.