There are a couple topics in this forum discussing winterization in general, like this one:
http://www.thorforums.com/forums/f17...24-sr-942.html
and this one:
http://www.thorforums.com/forums/f17...ta-sr-917.html
Both are relevant to the Axis as its water system is very similar. Fortunately on the Axis all the plumbing you need access to is underneath the passenger rear bed (on the 24.1). Typically if you're picking up your RV in winter the dealer will deliver it already winterized (ours actually flushed the system with water, showed us everything working, and then winterized it in front of us so we know how to do it in the future).