Microsoft Outlook
- Download the file and leave it where it is.
- Outlook: File → Options → Mail → Signatures → New.
- Pick the downloaded file as the signature, then set it as your default.
Using the newer Outlook? Copy the signature below and paste it into the signature box instead.
Gmail
- Copy the signature here.
- Gmail: Settings → See all settings → General → Signatures.
- Click in the signature box, paste, then save changes.
Gmail keeps the layout as long as you paste into the signature box, not into a new email.
Apple Mail
- Copy the signature here.
- Mail: Settings → Signatures → click the + button.
- Click inside the signature box and paste.
Apple Mail shows Inter where it is installed, and Arial where it is not.