How do you do this?

I have no idea what they are called...... but in a forum, below people's names, is some sort of description (either Deku scrub, Goron, Hylian warrior, in my case, Gerudo theif etc.) However I have noticed some people seem to have personalized these. How do they do that? This has been bugging me for some time now... Thanks in advance.

Check the rules. Once you have been a member for four months you're able to change your user title.

Sweet, thanks