Add to that list C-a " to view the list of screens. C-a A can be used to assign names to those screens. C-a [0-9] can be used to navigate directly to a specific screen. C-a C-a will swap the current and previous screen. C-a S splits the screen vertically C-a <tab> navigates to the next visible screen (there's no back-navigation). C-a q collapses all splits leaving the current screen visible. C-a d detaches from the screen session.

There are some other features, but with these you're using much of the power of screen. Takes a few days to get used to, but it's one of those "how did I ever live without this" tools.