install network-manager-openvpn
go to Network Manager (in system tray)→ Manage Connections, choose tab VPN → Add
type yours custom Connection name, in tab OpenVPN choose tab Required Settings
GateWay: 149.156.109.66
Connection type: X.509 Certificates
CA file: ca.crt, Certificate: username.crt, Key: username.key
Key password: yours password
go to tab Optional Settings
Gateway Port: 22
select Use LZO compression, Use TCP connection
OK, OK, open Network Manager once again and click Yours custom connection name in Connections