Signature by X
(1) You need two subscribing witnesses who witness the signature by X.
(2) The signer signs an X in your journal and on the document.
(3) Witness one signs the person's first name in the document and journal
(4) Witness two signs the persons middle and last names in the document and journal.
(5) Document the ID's and signatures of the witnesses in the document and journal
(6) Keep in mind that this is a very unusual notary procedure and is tricky.