In Outlook, navigate to Settings > Signature. Name the new signature "blank". Add in the following text in plain text: [[#]] name: Your Name [[#blank]]
Save
In the compose screen, select the blank signature. If you send an email applying this signature, the email will be sent without the graphic stamped signature.
Gmail
In Gmail, navigate to Settings > Signature. Click + Create new. Name the new signature "blank". Add in the following text in plain text: [[+]] name: Your Name [[+blank]]
Scroll to the bottom and Save Changes.
In the compose screen, select the blank signature. If you send an email applying this signature, the email will be sent without the graphic stamped signature.