WordPress Twenty Twelve Question

Hello,

I have set up my blog using the Twenty Twelve theme. I like it a bunch. What I don’t understand is that the sidebar only shows up on the homepage.

I’d like it to also be present on the individual post pages.

https://extremelyaverage.com <This is my blog, if you want to look at it to see what I mean.

I want people to be able to see the ads I’ve put in the sidebar, for my books, and also to see the “subscribe” widget. When I tweet the links to my posts, it goes directly to the individual post page and thus, I’m missing out on an opportunity to show people the subscription stuff.

Thanks,

Brian

p.s. Is the problem my floating widget thingy?