Our network will be healthiest when we have PTC holders running full public nodes.
This means allowing both incoming and outgoing connections.
Instructions for Bitcoin are here: Running A Full Node - Bitcoin
Patchcoin uses port 7801 for those instructions.
You can use this tool to check if the settings are correct. Open Port Check Tool - Test Port Forwarding on Your Router. Enter your IP address and port 7801.
The more people allowing both incoming and outbound connections, the better!
If you’re interested in supporting the Patchcoin network by allowing inbound connections, but need help opening up port 7801 on your device, post below for support. 
Arthur,
How will you run similar setting on VPN? You can post guide on how to for one of popular VPN provider.
Thanks
Many VPNs don’t allow port forwarding. Without it your node will not receive incoming connection requests from other nodes.
You can try searching “(your VPN provider) + bitcoin full node” to see if there are setup instructions for your specific VPN provider.