Apply the files with "kubectl apply -f XXXX.yaml" in this order:

wireguard-pvc.yaml
wireguard-secret.yaml
wireguard-deployment.yaml

Server MTU is 1420 by default and wouldn't normally need to be adjusted (most local Internet connections use 1500 MTU which allows for the Wireguard overhead without causing issues due to fragmentation)
Peer MTU should be set to 1360 to make sure the tunnels work over 4G/5G tethered connections without issues.
