Extracting a signature from a scanned document for insertion into an Outlook signature

Hello Experts,

I'm an Exchange administration consultant. A client has asked me to insert his written signature (which has been scanned to a jpeg) nto his Outlook signature. While simply pasting the JPEG into the signature creation wizard is easy enough, I need to extract the signatue...not the background...from the JPEG. I suspect Photoshop will do this, but I have little to no experience with it... I suspect I need to create a layer from the JPEG and convert the written signature to a GIF....The signature image is attached.

Thanks...
clientsignature-copy.jpg