xize11
19
I think this video is straight forwarded:
The part of the qr code has also a tab to copy the configuration, this is the configuration you want to add to your other router 
Wether you need vxlan here depends if you need layer2 capabilities such as vlans, in many cases you don't need it.
If you want to reach a device on lan, you can allow that by the settings here:
optional:
You can also portforward to your wireguard peers from the server and to lan.
If you for example use a server or application, and want to hide the ports for being open under a layer of encryption this is possible, also the open port the wireguard server hosts on appears to be closed from port scanners due to it is using udp, and wireguard does not respond to unsolicitated connections.
You can do that like this: