Few different ways to accomplish this, but I would just key the green screen footage and then add a glow effect. Change the "Glow Based On" to Alpha Channel, select my glow colors, glow radius and glow intensity. Finally I would change the "Composite Original" to On Top.
Johnny Cuevas, Editor
"I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work."
---THOMAS EDISON on inventing the light bulb.