How to always know which is the prefix key in tmux
Put it in the status bar. First check what is already in the status bar by issuing:
tmux show-options -g
Look for " status-left" it may look like this:
status-left "[#S]"
If the prefix key is Ctrl-b, and the present setting for the left part of the status bar is
"[#S]"
Do:
tmux set -g status-left "[#S] Ctrl-b"
No you will always have a reminder what the prefix key is.