[Staff/Students]
Depending on the email client you are using, you have to access it through one or another configuration option.
For the Webmail gateway, you can find how to set up your signature at:
Personal Webmail Help - Within the Identity settings.
Webmail Help Students - Within the Identity settings.
Help Add signature in Outlook
Help Add Signature in Thunderbird
On the other hand, you can generate an institutional signature that you can then paste on your signature via link:
UPM Institutional Signature Generator
and follow the instructions on that page.