How do you fix a transmission that is skipping gears?

The transmission is skipping gears on my 1994 Mustang V6. What is the best way to fix this problem without getting a transmission rebuild? When I manually shift it into 2nd, the gear works, but it skips 2nd in Drive.|||if it,s automatic and has a modulator on the transmission then change it.|||Sorry, but for the amount of tear down you'll need to repair it, you are looking at a basic rebuild. Shop around, but you will find a rebuild on the AOD-E in your Mustang will cost around a thousand or so to fix