Change signature appearance
1.Open the Preferences dialog box, and then choose Digital Signatures.
2.Under Appearance, click New.
3.Enter a title for the signature appearance, and then do any of the following:
Select No Graphic if you want the signature field to contain only the icon and other selected items.
Select Imported Graphic to use a graphic signature, and then click PDF File. (Your image file must be in PDF format.)
Select Name to use the signature profile name for the appearance.
4.Select any text items you want to appear with the signature on document pages, and then click OK.

Signature Topics
Creating a new signature appearance in complete Help