Assuming this is a linux VPS, cPanel/WHM would be a great way to simplify your life.
If you don't want to pay the licensing fees it is still possible to install an email server however things statr to get complicated if you are not familiar with CLI interface.
To explain an actual how to, it would be too long. So i'll mare another assumption : You can change your operating system. Change it to Ubuntu and follow this guide: https://www.digitalocean.com/commun...stall-and-configure-postfix-as-a-send-only-sm atp-server-on-ubuntu-14-04
You'd still need to set your rDNS and follow your providers rules on emails.
If you want an answer for a specific operating system{windows included} or setup, reply with info.
Yes, as stated up maintaining email server on CLI would be difficult for some.. You can use any control panels like cPanel for the easier mailserver setup but you need to comply with the Rules.