If you have the "Approver Signature On Check" preference enabled, this is how to add a signature for your payment approvers.
NOTE: In order to add a signature for a user, you need to have permissions to edit the payment workflow.
Navigate to the User List page. At the top under "Options", select "Manage Signatures".
This will change the view of the page. Only users with permission to approve payments will be visible. Users with a signature already on file will have their signature displayed, and users without a signature will have text that says "no signature on file". Next to this, there will be an "Upload" button that will let you select a signature file to upload.
For best results, we recommend using a .PNG file with a transparent background, and as little extra space around the signature as possible.