Go tohttp://www.cbseresults.nic.in/ or whatever your board is.

Enter your details and download the result.

Print it out and then sign on it. When you sign the page, you are essentially declaring that this is the original document issued by CBSE, and it has not been manipulated in any way. That is what Self-Attestation means.

Scan the signed page, and upload it on the website.

The scanned image may require resizing, so that the file size is less than 150 KB.