Persistence and Post-exploitation on system outside of LAN network?

Hello, it's been a while. It's been a while since I have posted on here, and I really want to get back and contribute to the community. I have been working on a lot of projects, and I am looking forward to spreading more knowledge and learning more as well.

Well, I guess I've been playing around with my household computers and sort of doing makeshift "labs".

Hypothetically, let's say I was able to compromise a system outside of my LAN network with metasploit. I portforwarded my port 4444 and set my listener so that the connection from the victim's external IP address (let's say 123.456.789) reaches my external IP, and because of the port fowarding, the connection goes to my machine where the listener is set up (let's say 192.168.1.187). I hope that didn't sound stupid BTW. I get a meterpreter session. I want to maintain access, but since it is outside of my network, what should I do so that I am able to come back to this system. For example, how can I implement a netcat backdoor, or the metsvc service, but for that particular system?