I challenge any one reading this to try this at least once. I hope you make this routine!
Every small purchase you make adds up. Every snack, energy drink, coffee that's not brewed at home, can make a difference. I never thought about it a lot until I realized my paychecks were thinner and thinner as the weeks went by (if you're paid biweekly like I am). How could this be? Small purchases add up.
Try this: For one month, or start smaller if you wish, don't splurge on the little extras. Brew coffee at home and have a travel mug (it's better for the environment, anyway) and put the $2 in a jar. Want a sandwich for lunch? Make your own. Put $5 in the same jar. After a month, or even a week goes by count the money in your jar. You'll be very shocked. I know I was. Being aware of what you are spending your money on is crucial in setting yourself up for a more stable future.
Use that money as either a reward after a few months/year or pay down your student loans. You'll thank me later.