If you are a noob with a domain and need to host your own mail server, you need mail-in-a-box. Look it up. It runs on a VPS and configures email and even a static site for your domain. It also comes with a dashboard where you can create additional email accounts.

I am actually thinking on writing it since long ago... But not motivated enough... :/

I'd read it! As would others, so perhaps knowing you have an interested audience might motivate you further?

You sort of almost already did with your reply. Just copy it, add pics, add code, add more text and details,

Done.

Do it.

Please find some time to write it. It would be a great resource for self hosting.

Another vote for a blog post, please.