hypertext in email signature

2009 iMac Mountain Lion 10.8.5

Apple Mail 6.6

i am sending out emails to multiple people that will include the exact same text in the body of the email. to avoid a copy and paste routine i created a signature that contains the entire body of the email, i just need to add the subject, necessary personalization and email address for each email. within the body i want to include an html link. is there a way to get that to transfer into the signature? when i tried, it did not come up as linkable hypertext. i know i can do this in windows outlook by simply copying and pasting from a word doc into the signature field. just wasn't sure about apple mail.

thanks for the help!