Anyone know HTML?

I've decided I hate Blogger's templates. So being the industrious graphic designer that I am, I made a new one. Fairly simple, done and exported from iWeb. (I want to keep it simple for now).

But I don't really know what the HTML editor in Blogger is asking of me to get this to work. It tells me I need to skin tag, and I really don't know how to accomplish that. 

Has anyone made custom temps for Blogger? I could use your help.

Cheers.