I applied by SDS , I'll provide with the list of optional documents which are somewhat necessary nowadays. You'll also need to upload the necessary documents such as LOA , GIC etc.
1.SOP
2.Affidavit of support from your sponsor
3. Salary slips + tax returns
4.GP/Provident fund if your sponsor has any
5. Bank statements (4/6 months , it shows that you have some liquid amount)
6. Original Property docs scan , valuation certificate
7. Property inheritance docs from the owner , if they want to inherit you the share of their property.
8.Letter of Recommendation from professors , managers( if you did some job)
9.Police certificate
10.Family registration certificate (FRC)