OpenVPN QoS

Hi,
I’m trying to apply QoS to give priority and guaranteed bandwidth to an openvpn connection over the rest of the traffic on the LAN. What would be the most effective way to do it? Can I mark all the connections that are destined for the external openvpn server and then apply queues to prioritize and guarantee all the traffic that goes to the openvpn server?
esencario 192.168.1.246 (pc which establishes openvpn) —> mikrotik —> internet —> openvpn server (server.openvpn.com (example))
Thank you!