I would like to create a head turn effect by adjusting the horizontal slider as seen in this youtube tutorial video.
The effect works great when I move the slider manually, but I can't figure out how to move the slider very slowly so that it fills up a 15-20 second video clip from the parameters of horizontal displacement of -7 to 6. I'm a noob, so this is new to me. Thank you for your help.
Youtube tutorial: https://www.youtube.com/watch?v=zbYfxrsJUqI
Screenshot of where I am in the process: http://imgur.com/a/5PNvp
You might want to read up on keyframing parameters in AE. That's all you need to know.