To receive margin, you will need to send a letter to the Kotak Mahindra Bank to mark lien in favour of Kotak Securities against the Fixed Deposit/Bank Guarantee.
In the form of an approval, you will then receive a written acknowledgement from the Kotak Mahindra Bank confirming the pledge in the prescribed format.
Check the list of documents you will need to submit to Kotak Securities to get margin on your fixed deposit.