Tmux

Note, most listed single-character commands are prepended with the leader key combo.

General

ctrl+b leader key combo. This may be ctrl+a for some.
d detach
? list shortcuts
: prompt

Sessions

tmux new -s <name> new session
tmux a -t <name> attach to session
tmux ls list sessions
tmux kill-session -t <name> kill session
:new new session
s list
$ name

Windows

c create
w list
n next
p previous
f find
, name
& kill

Panes

% split vertical
" split horizontal
x kill

ITerm2 mode

add -CC to the tmux command