With the IRS filing deadline just a heartbeat away, many Americans will be in a rush and make mistakes on their income tax returns. MainStreet provides a few tips to help you avoid the most common filing errors especially if you are doing it yourself. First, don't leave anything blank on your return, especially those check boxes. Always check the printer: it's not uncommon for tax payers to leave behind a worksheet or schedule. Lastly, enter your social security number correctly.