You can download the SPARK application here : https://sparkmailapp.com/download
Set up your mailbox(es)
To set up your signature, simply go to the Settings menu:

Select the "Signatures" tab:

Click on : + ADD A SIGNATURE
Go to the HTML section

In your user interface, in the "Mail signature" section, select and copy the "HTML code" displayed below the signature:


In Spark, click on the "HTML" button and paste your code:

That's it, your signature is set, and will be automatically updated when you make any future changes.

**When you exit "HTML" mode, you can also add text to your signature.
Now you can test your signature by sending yourself an email BUT BE CAREFUL: the link in your signature is NEVER active when the email is sent, only when it is received.