I'm willing to help you much as i can (although i need help myself lol) ..
first thing i read the tutorials written by willz.. then read the official document..
all can be found here:
http://www.msgpluslive.net/skins/resources/
and you need an XML editor
I started with notepad 2007 XML editor.. then i got the free trial version of Altova XMLSpy.. i found it easier to use.. specially when using the schema (at times..at times it gets bit confusing)
and you need to know bit about the XML language.. i've learned thro practice and just reading in the reserces link above.. and some hep from other members..
Good luck