Ctrl+b "– split pane horizontally.
Ctrl+b %– split pane vertically.
Ctrl+b arrow key– switch pane.
Ctrl+b, don’t release it and hold one of the arrow keys – resize pane.
Ctrl+b c– (c)reate a new window.
Ctrl+b n– move to the (n)ext window.
Ctrl+b p– move to the (p)revious window.\