Match moving with a composite

Hi. I am trying to insert/composite a roto object into another piece of footage. Sounds simple enough, lol, except that for me it isn’t since I am pretty new and get bigger ideas than I can readily execute. I am trying to insert an image into the ECU pupil of a character. There is a little eye shake and jitter, and I tracked the pupil no problem. I have the image I am inserting transformed and resized, but I don’t know how to match move the insert into the pupil so that it naturally follows the pupils movement. Do you have any recommendations?

@ami Check out the Match Move and Stabilize Images tutorial.