Xwiki customize templates

Hi, I'm looking to use xwiki, though would like to do some custom skins and templates for my site. I was looking at the various vm files under the "templates" directory, though am becoming horribly confused as to the flow, page life cycle, and generally how everything is connected. Is there some good resources I can read about how everything fits together and also possible some sample applications? I'm not really sure where to start or even how the main page for xwiki is being generated...I tried looking through the xwiki website, though customization documentation seems sparse, though I may have just totally missed something...thanks in advance... Thanks, Josh