How do you fill auto trans fluid to a 1996 Saturn?

Answer 1

The Saturns, and in fact MOST modern automatic transmissions are what is considered "sealed", meaning that there should be no need to top off the fluid unless there is a leak, and if there is a leak, they obviously think you should take it to a shop.

However...

Part way up the transmission, on the side, is a fill hole that has a plug in it. Remove the plug and add fluid until it starts to run out. A service manual should be available in your local library, and there should be a picture to show you which is the fill hole.

Saturn recommended that you have the Transmission Fluid and filter changed periodically. Some shops offer a "power flush", in which clean fluid is forced through the lines and the torque converter. Not a bad idea if it hasn't been done before.