How to add the sidebar back into the new default theme of WP3.2 – Twenty Eleven.
Twenty Eleven is a very versatile theme, however, the ‘missing’ sidebar on single posts or pages is quite disturbing for some users, loosing their advertising space or the main navigation.
To get the sidebar back is not that simple – style.css is quite complex, and the layout of a single post or page is done with a clever use of a specially introduced css class in the body tag. Check the whole post
To organize posts into three columns (edit: semantically more correct would be to call it ‘three posts per row’ as this is the way the posts are organized), you first need to generate a column dependant css class for each … Check the whole post