tmux new [-s name] [cmd](:new) - new session
tmux ls(:ls) - list sessionstmux switch [-t name](:switch) - switches to an existing session
FWIW: I didn't produce the content present here. I've just copy-pasted it from somewhere over the Internet, but I cannot remember exactly the original source. I was also not able to find the author's name, so I cannot give him/her the proper credit.