i.e. This Boeing 757-200 has 8 emergency exits. These are clearly marked throughout the passenger cabin. Your nearest exit, which may be behind you, is being pointed out to you now by the Cabin Crew.
--pax point and laugh and you try and keep a straight face as No. 2 does a moony in the rear galley--
If oxygen is needed (and the cabin crew do need it), masks like this will automatically drop from the panel above your head.
Place the mask over your nose and mouth, put the band over your head and breathe normally.
--Yeah right... as elastic pings and tries to sever your ears--
etc etc...