Screen Sharing --- Mac

I am working with someone who is having difficulty being able to set up the Categories feature on this site. Now that I have done it - well that seems easy. But it did frustrate more than a little. It occurred to me, if I did a screen share it might be easier than the screen shot & email approach.

Is there a simple way to screen share with another Mac user? Would Face Time phone calls work if people turned their iPhone around? (I have never FaceTimed, so I don’t know anything about that process.)

Maybe a little dated, but this article might help:

And from Apple:

Have fun!