How do I activate XM?

Back in 06 when I bought my 2006 Vue my dealer told me it was XM ready if I ever wanted it. Well, I'm interested in it now but I can't find out how to activate it. I looked in my manual and listened to the OnStar CD. Also I couldn't find anything on the XM site.

you will have to contact xm, go to there website and there will be a number there to call for activation