$ tmux new -s 'example_session_name'

Creates a new tmux session with the name 'example_session_name' which is very powerful and will exist even if you close out of the terminal.

Once you launch use <Ctrl + "> to split the window horizontally or <Ctrl + %> for vertically split and moving between windows with <Ctrl - Vim_Direction> You can detach and go back to shell at any time with <Ctrl + d> then reattach later with tmux new-s 'example_session_name'. If you forget the name a simple tmux ls show running sessions.

cheat sheet