oceanbluesky on "Adding a second sidebar to the basic twentytwelve layout?"

Hi, I'd just like to create a twentytwelve-child modification displaying blog pots in a center column with widgets in columns to its left and right...super simple straightforward modification of the otherwise standard twentytwelve theme.

How would I get started? Just duplicate and rename the sidebar.php file to sidebar2.php and then modify the style.css? (Is that it?)

thanks