Good for you for wanting to live more within your means. There are budget worksheets that you can use. It's always helpful to see your expenses on paper so you know where your money is going and what areas you can start to cut back on.
I don't know how old you are so I'm not sure if your parents support you financially or what ever but if they do just keep like $10 bucks on you ( saying that your parents will pay for food & stuff) and keep the rest at home so u can't spend it. You can also put your coins in a box or jar and over time it will add up & you can take it to a coinStar & get bills ( this has help me lots!!)