Here is the step by step guide you can use to add a signature in a panel. 

1. Login to your Reseller panel. 

2. At the Right-Top Panel , Click on profile settings. 

3. Click on modify option and add the signature in the signature section. 

Example:  Regards,   

                     Team XYZ   

                     support@xyz.com | www.xyz.com 

4. Click on Save. Signatures are added successfully.