My dad has a rubber tree that he has been keeping for the past 40 years or so. Its in our living room so its kept pretty small through consistent trimming. What would I have to do to make one of these trimmed branches take seed and begin its own rubber tree in a new location?

This is a bonsai forum. But to answer the question you could air layer it. To get seed a plant has to flower as far as I know they do not.

I never seen a branch taking a seed.
You want to make a cutting from a branch? Of do you want to start from seed?