Unfortunately Apple Mail has been historically unsupportive in enabling HTML email messages or html signatures. There are ways around it, but require knowledge of html and you have to jump through some technical hoops.
We created a tool to enable you to copy and paste your seal into Apple Mail.
Go to applemail.privyseal.com
Follow Steps 1 & 2 and then return here for Steps 3 onwards.
In Apple Mail Click ⌘+ (or Choose “Mail”, then “Preferences” and then “Signatures”)
Before exporting your signature go to your signature settings and make sure
the option to "Always match my default message font" is NOT filled in.
- You can assign the signature to all or to a specific account.
- Want to modify your signature? Make the change, click the Green button to Save the change and repeat the steps above.