There's rarely one huge things that you can save on but if there are lots of small $10 things going out of your bank each month those can really add up.
A written cash budget can help. There are a number of great free budget templates online. I started one for curiosity over ten years ago, and never quit. Keep all your receipts and enter them in the correct categories. Keep track of everything, including cash for little things like a cup of coffee etc. You will see quickly WHERE your money is going and you can make needed cuts before expenses get out of hand. Cash "leaks" are the most wasteful and easiest spending to control...with a written budget. After I did this instead of always having an empty wallet, now I find that there is ALWAYS cash in it, and most of the time more than just a few dollars. Of course it will take discipline, and a little time, but the rewards can be great.