Hey,
It's very simple you just need to visit the head office of the educational institution printing your educational certificate. They hopefully will need you to submit a affidavit stating that you have changed your official signature.
After submitting few the copies of the documents they will take some time to process it.
In case if you want to know about some specific information you can let me know. I will help you with the procedure.
Hope that helps.
Thank you
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