How to put description under username?

How do I put a description under my username? I see it on some members like under their username there are words like "writer", "mother or two" "scholar", etc. How do I do that? There are no input fields on my Memcenter or do I need to have a certain amount of points? Thanks in advance.

If you click on Memcenter, you will find a list of clickable options on the left side.

If you then click on "ATS Store" you will be taken to a screen where you purchase "Custom Titles" for the first and second lines.

The first costs 750 ATS points, the second costs 500 ATS points.

The "Writer-Fighter-Scholar" titles are for the Short Story Forum - Debate Forum - Research Forum respectively. They allow you access to participate in their correlated Forums and must be obtained through demonstration of posting habits on ATS as well as a request to a Moderator.

Hope this helps...