How to be and recognize an emotionally mature partner.

I want to go through life with someone that is emotionally mature, but mainly I want myself to be that , but… Do we know how to become that? Do we know how to recognize it in someone?

I am a firm beleiver that before you ask someone to offer you something you should be capable to offer it, always start with yourself.

Let´s define what the traits of an emotionally mature person are so that way you know what you need to work on, and also so you know how to recognize it in people that you want to spend time with.