Making your blog snazzy: Step One

So you've just downloaded a generic-y, but somewhat neutral and pleasant new template for your nascent blog. What's the next step? Have something go wonky in the code and not be able to find it, of course...

My header is currently weirdly centered and hovering on top of the posts and it decidedly is not supposed to be doing that. Blankly poked around the code hoping there would be a section that popped out and said, "Hey, fix me here!". Alas. Will take to the experts in the next few days...

EDIT: Figured it out (on my own) after a couple of hours of farting around on Buzzfeed and Reddit!! Small victories. The header is now in place.