The process of renewal of the EWS certificate remains the same as the process for applying for a new EWS certificate. You have to visit the same issuing authority with the updated set of financials for the new financial year to get a new EWS certificate. The mentioned documents you required:

• Duly completed application form with Rs. 2 court fee stamp.
• Certification from two gazetted officers.
• Education records duly signed.
• Aadhar Card.
• Address Proof (Voter ID, Ration Card, etc.)
• Rs. 10 non-judicial paper declaration according to G.O. 1551 and I.T return, if any/pay slip.

Hope it would be helpful.