Blog Templates for Dummies?

I need it 'cause I am one. I have been so bored with the way my blog has looked that I spontaneously decided to change it last night...without thinking about the consequences if I didn't save my original template! This is NOT how I envisioned my new, updated, hip blog to look, this is only temporary. I blame it on starting a project at 10pm, being extremely tired, and not knowing what the heck I am doing. Just wanted to let you know that this is NOT the finished project by any means. Why do I start such projects so late at night?!?!?