Many people try to register for tax returns by themselves and end up making a lot of mistakes. You may think of saving your money, but in reality, you would be wasting your time and effort that you can use on other things.  Here are some common mistakes that people make while filing a tax return: Missing deadlinesMentioning incorrect figuresTrying to claim the wrong expensesForgetting to declare salary and benefits from other jobsImproper recordsEntering the wrong tax code