Instructions to make library available outside home network

I just installed Roon today.
I’m having Roon Core and my music on a QNAP NAS (QTS 4.4.2). At home everything I need works like a charm without any special configurations.
Can someone provide or point to instructions for dummies, on how can I access the library from outside home network, using the iPhone app?
Thank you.

Roon does not official support this. You might find some information on setting something like this up in the Tinkering section.

yah, lots of stuff in #tinkering – check out the zerotier topics