I always search for this so I will write it down here.

Client

cd /etc/wireguard
wg genkey | tee privatekey | wg pubkey > publickey
vi wg0.conf

[Interface]
PrivateKey = 
Address = 10.9.0.X/24

[Peer]
PublicKey = dg1cKCId81d6h5cWUQ61BMHksBbi0FdFnitjxDuOuno=
Endpoint = vpn.danman.eu:51820
AllowedIPs = 10.9.0.0/24
PersistentKeepalive = 25

wg-quick up /etc/wireguard/wg0.conf
systemctl enable wg-quick@wg0.service
systemctl edit wg-quick@wg0.service

[Service]
Restart=on-failure
RestartSec=5s

Server

systemctl stop wg-quick@wg0.service
vi /etc/wireguard/wg0
systemctl start wg-quick@wg0.service

Reload

wg syncconf wg0 <(wg-quick strip wg0)