After an audit is scheduled, the first thing to do is look over your return and refresh your memory. Examine the items the IRS questioned in its notice of audit, and organize your records accordingly. Then, check the rest of your return and gather proof for items about which you're unsure.
You can authorize an attorney, CPA, enrolled agent, or other individual recognized to practice before the IRS to represent you at the examination. You don't even have to be there.
If you attend the audit, take only the records related to the items questioned in the IRS notice. Do not volunteer extra records; if the agent sees them, it might suggest new areas for investigation. Don't let the IRS hurry you into an examination until you're ready. An agent may even appear at your home or place of business and try to begin an audit immediately. Resist this pressure, and reschedule the meeting at your convenience.