I've created a port forwarding video to help people hopefully set up port forwarding reasonably securely. The only thing that I didn't go over is how to setup Let's Encrypt with OctoPi, which would require a completely separate video.
I completely understand the discussions concerning VPN vs. Port Forwarding. I do reference the blog post for safely securing your OctoPi/OctoPrint installation as well as Gina's writeup on how to setup haproxy. For those that decide to go with port forwarding, I wanted to provide a way to do it that is reasonably secure. Here's a link to the video:
I would be interested in people's feedback. The link is still unlisted. So, if there are significant issues, this isn't going far and wide.
[Edited: Replaced old video, which was deleted with the new video.]