Help With Tumblr Layout

I'm not really good with HTML and CSS codes so I want to ask for help with my Tumblr layout. I've been working on this for the whole sembreak but I can't get it through... Frustrating, really. :|

What I want  is to make the Facebook and Twitter buttons inside the post. Somewhere in the white paper-like thing, not in the yellow background.

I hope someone could help me with this!