Put your debit card away. It's pretty easy to grab that thing and use it, huh. You're less likely to buy impulse items if you have to dig out the check book or use cash. Vow to never get cash from the ATM that charges you a fee. If your bank charges you fees for checking, look for another bank.
Now that you have the checkbook in your possession again, there are some things you can do. First, start a coin can.
Write the check at the grocery store to the next highest dollar so you get some change back. When you get home, put the coins in your new 'savings' can. Every time you have a few coins in your pocket, add them to the can. A lot of people save $300 a year doing this simple thing.
Use coupons? Rebates? Put that money in your coin can when you get home.
Talk yourself out of buying something extra at the store? Put that money in the coin can.
Got an expensive habit, like tobacco or alcohol? Try to cut it in half. You're already used to the money leaving your pocket, so put the 'saved' money in the coin can.
If you usually have cash in your wallet, can you add a dollar a day to the can? Or even just a dollar a week?
Now that you have your own little stash at home, use it to your advantage. Do the debt snowballing thing to stop paying interest. If you saved up $30 in your coin can this month, take it to the bank and then pay an extra $30 on your credit card payment, car payment, etc. You can get a good idea of how much your loan is costing you (and how much you'll save by paying a little extra each month!) by using an online 'what's missing' calculator like this one - http://www.hughchou.org/calc/missing.cgi . Hugh has a ton of different calculators to help you.
Round up to the next dollar when you subtract the check amount in the register. Write a check for $39.03? Subtract $40. By the end of the year, you could have another $300.
You can also write 'saved' amounts on a calendar. This comes in handy when you get back from the store and only used $2.15 worth of coupons, or decided not to buy that bottle of water from the convenience store. Put that amount on your calendar. At the end of the month (or sooner!), make an extra online payment on your credit card. Seems like another bill going out, doesn't it. But it's money that you would have spent in your previous lifestyle. If it's just a few dollars at the end of the month, add it to your usual payment.
Need to buy a car? Buy a used one instead of the new hybrid you really want. The money you'll save over all by lower cost, insurance and taxes will more than offset what you'd save in gasoline costs. I hate this one, but it's true.
Sometimes you have to look at quality over cost. We could save $500 by buying a used riding lawn mower, but by spending the extra, we'll get a three year warranty and know that we aren't buying someone else's problem. We'll take good care of it, so it should last us for as long as we're here or will need one.
Rent a movie instead of going to the movies. More popcorn, whatever drinks you want and as much as what you want, plus you won't miss part of it if you need to make a pit stop halfway through. Write down what you normally would have spent on the calendar.
Try more private label stuff at the grocery store. Some of it is lousy, but many items are just as good as the name brands. Jot down the price difference, then add it up when you get home. Put the difference in the can, or write it on the calendar.
Every two years, check around for insurance rates. Insurance companies have a way of sneaking the rates up. Look for an insurance broker that doesn't represent just one company or look online.
Ideally, come April 15th, you don't want to have to send a check, but you also don't want to use the IRS for a savings account, either. But some people qualify for money back that they didn't send to them to begin with. Don't go buy that new computer! Pay off your debt or put it in a savings account.
Just got a raise at work? Lucky you! Use that extra money to pay off debt or save.