Hi Ishika,
It is very simple you have to just sign on the photo copies of your document and they will be considered as attested. Attesting means that you are making sure that the documents that you are submitting are genuine and are submitted with your due permission.
Predict your colleges using our JEE Advanced 2020 College Predictor - https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer
Feel free to ask doubts in the Comment Section.
I hope this information helps you.
Good Luck!
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