Enabling Remote Access To Home Network

Hey all,

I'm trying to setup my C3700-N600 router to allow me to remotely access the iMac on my home network from outside of my network - i.e., I'm trying to access it from my campus laboratory. I've scoured at least 30 or 40 sites now and none have given me a straightforward way to do this that doesn't include setting up something like the genie app. Port forwarding steps and MAC addresses are what I'm expecting the answer to contain (unless there's another way).

A little background: I'm attempting to use Back to My Mac from my Macbook to remotely access my iMac at home. I've already configured my iMac and Back to My Mac so that it works when I'm on my home network.

Thanks!