Steps:

1) install wireguard

2) enable ip forwarding

3) create subnet for clients

4) create routing rules on host

5) create routing rules on router

# https://lwn.net/Articles/748582/

# ip link add wg0 type wireguard

# ip addr add 10.0.0.1/24 wg0

# wg set wg0 private-key <private-key-file>

# ip link set wg0 up

# https://www.wireguard.com/quickstart/

# Another guide to look at:

# https://www.ckn.io/blog/2017/11/14/wireguard-vpn-typical-setup/