5. You have no clear priorities. Lacking motivation? Set a goal. Budgeting merely for the sake of budgeting is a chore. But when you have your eye on something you want, managing your spending becomes -- dare I say it? -- a pleasure. It's easier to cut back when there's a light at the end of the tunnel.

Think of it this way: A budget helps you manage small expenses today so you can buy bigger stuff and have more fun tomorrow. So ask yourself what you hope to gain from your experience.

6. You've set unrealistic targets. Need help getting started? Here's a flexible blueprint that you can adjust to your own financial situation: Use 30% of your take-home pay for housing, 10% for utilities, 15% for food, 10% for transportation, 5% for clothing, 10% for debt repayment, 5% for entertainment and 5% for insurance and miscellaneous expenses. That leaves 10% for savings or special purchases. (See Kiplinger's Cost-of-Living Reality Check to learn more about anticipating your costs.)

Remember, though, that this is simply a guide. To set targets that are realistic for you, track your spending for at least one month. That way, you'll see how much money you have and where it's going so you can make the necessary fixes.

7. You don't have a safety net. Unexpected costs can derail even the best-laid plan, hurl you into debt and require months of adjusting before you can get back on track. So priority No. 1 for your budget should be to save up a small cash reserve for emergencies. That way, if the car breaks down or you make an unexpected trip to the ER, you won't undo all your hard work.

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If existing debt is getting in the way of creating a successful budget, consider getting help. (To find a nonprofit debt counselor, contact the National Foundation for Credit Counseling.)

8. You quit too soon. Don't be discouraged by failure. It took me six years of trial and error to figure out how to budget successfully. (I hope that by learning from the mistakes I shared above, you'll get on track much sooner.) I'm glad I stuck with it. I'm no longer enslaved to living paycheck to paycheck. I've paid off my student loans and bought a house. Plus, I've been able to pay for fun stuff, such as vacations, without going into debt.

Even now, there are months when I meet my spending targets and other months when I miss terribly. But I keep a big-picture view: My successes outnumber my failures. And the peace of mind and control I've gained over my finances have made budgeting well worth the effort.