update cheat sheet comment

.tmux.conf

@@ -64,11 +64,15 @@ run '~/.tmux/plugins/tpm/tpm'
 # CHEAT SHEET:
 #
 #   update working dir of a session to current dir
-#   :attach-session -t . -c '#{pane_current_path}'
+#       attach-session -t . -c '#{pane_current_path}'
-#
-# save pane layout          prefix C-s
-# restore pane layout       prefix C-r
 #
 #   swap two panes
 #       on one                prefix m
 #       on the other          :swap-pane
+#
+# REQUIRES TPM
+# git clone https://github.com/tmux-plugins/tpm ~/.tmux/plugins/tpm
+#
+#   save pane layout          prefix C-s
+#   restore pane layout       prefix C-r
+#