In your rush to finish and file your tax returns, take special care with the little things.

Today, the IRS listed several worthwhile steps to take to avoid last-minute tax-filing hassles and errors. They include:

• Making sure you've entered the proper identification numbers, including Social Security numbers and bank-account routing numbers. A friend of mine made a mistake keying in her child's birthday; as a result the return didn't reflect a $1,000 child tax credit. The IRS might have found the error later—its software can compare birthdays and Social Security numbers from year to year—but in the meantime, had my friend not caught the mistake, she would have had to wait for the correction and her additional refund.
• Checking the right boxes for exemptions, and having only one filing status (single, head of household, married filing jointly, married filing separately.)
• Signing and dating the forms, and sending them to the right address. If you're filing electronically—a wise move—you'll need an electronic filing personal identification number (PIN) in lieu of a signature. If you don't have one or don't remember yours, follow these IRS instructions.
• Keeping a printed copy of the return. You might need it later for financial planning or in the rare event that you're audited. On that theme, Consumer Reports offers perspective on the types of items that trigger audits, and how to prevent them.

You should watch out for these other errors, too.

Using tax software to prepare and file your return electronically helps you avoid errors, save time, and speed up your refund, but you can still make mistakes. So check a print-out of your return before you file electronically.

If you're at all uncertain you've done things correctly, file for a six-month extension, using IRS Form 4868 (PDF). You're still expected to pay what you owe. This year, however, the IRS is offering some relief to households that have experienced unemployment for 30 consecutive days in 2011 or 2012.

The IRS seemed on the case today; I called at 8 AM with a last-minute question about filing a return for a deceased person. I got a phone answer in about 15 minutes (and later found the same information online). There's no guarantee that you'll have the same success, but it's worth trying. IRS phone reps are open for questions from 7 AM to 7 PM, in all continental time zones (Hawaii and Alaska taxpayers must use Pacific time).