In Gmail, click the gear icon (top right), then See all settings.
On the General tab, scroll to Signature. Click Create new, name it, and click Create.
Click inside the signature box and press Ctrl+V to paste.
Under the box, set it as the default for new emails and replies.
Scroll down and click Save Changes.
Outlook
Add it in Outlook
Click Copy signature above.
In new Outlook or Outlook.com: Settings gear, then Accounts, then Signatures. In classic Outlook: File, Options, Mail, Signatures.
Click New, give it a name.
Click inside the signature box and press Ctrl+V to paste.
Set it as the default for new messages and replies/forwards.
Click Save.
If pasting ever strips the styling, come back to this page and copy again, some editors have a "paste as plain text" mode turned on. On a phone, this is easiest to do from a computer. Questions, just ask.