Where to put the power steering fluid in a 1985 cougar?

There is a Power Steering pump under the hood in front of engine, it has a pully that is driven off a belt. Read the cap on top of the plastic reservoir that is attached to pump (to make sure it is power steering) and there should be a dipstick connected to cap. Your owners manual should specify what type of fluid to use and only fill fluid to appropriate level (that is denoted on the dipstick that the cap has)

PS- do NOT get any dirt in there