-ctrl a c -> create new window
-ctrl a A -> set window name
-ctrl a w -> show all window
-ctrl a 1|2|3|… -> switch to window n
-ctrl a ” -> choose window
-ctrl a ctrl a -> switch between window
-ctrl a d -> detach window
-ctrl a ? -> help
-ctrl a [ -> start copy, move cursor to the copy location, press ENTER, select the chars, press ENTER to copy the selected characters to the buffer
-ctrl a ] -> paste from buffer
How to start screen:

-screen -DR -> list of detached screen
-screen -r PID -> attach detached screen session
-screen -dmS MySession -> start a detached screen session
-screen -r MySession -> attach screen session with name MySession
Advanced:

-ctrl a S -> create split screen
-ctrl a TAB -> switch between split screens
If you created a new split screen, the current window is empty. either select an existing window (ctrl a “) or create a new split screen (ctrl a n).

-ctrl a Q -> Kill all regions but the current one.
-ctrl a X -> remove active window from split screen
-ctrl a O -> logout active window (disable output)
-ctrl a I -> login active window (enable output)