Your Income Tax Return is referred to as an annexure less return. This means that no documents or proofs have to be attached along with your tax return. The relevant proofs and certificates (like rent receipts, investment proofs statements) are absolutely essential to be maintained.
However, those must be kept safely by you in your own records and need not be sent to the department upon filing. If the Assessing Officer sends you a notice or you have to justify these deductions under any circumstance, you will need such proofs.
Otherwise, all you have to do is file your income tax return online.