For starters, choosing the right ITR form depending on your income from different sources is the first step to ensure an error-free tax filing (see graphic). For instance, if you are a salaried individual who has made capital gains on sale of equity shares, you cannot file the simple ITR-1 and will have to opt for ITR-2. But, if you have dabbled in the derivative markets, you need to choose the much more complicated ITR-3 or ITR-4 as income from futures and options (F&Os) is considered business income. Similarly, it is important that you reconcile all the auto-populated information in the ITR form with the individual income certificates to avoid getting a tax notice from the taxman. As you gear up to file your tax returns, Mint gives you a comprehensive guide on two important steps involved in the process.