This probably sounds stupid but...

[-Samantha-]

You know the little thing that comes up underneath you name?
You know, that says junior member, senior, Whatever. Well, how do you change it? I notice a lot of you have got your own thing underneath your name, i and i just wanna know how to do it.

Im sorry for sounding like such a dick.
Thanks.

[Rag Doll]

You need, I believe, 500 posts. Somewhere around there.

Then you go to the User CP on the upper left and change it there.

[holland25]

Yes, it's exactly 500 posts.

[Blackball_]

five hundred posts.

[Outerspaceman21]

Yeah, once you make 500 post, you can customize that feature. To custmize, simply go under User CP, then click on "Edit your Details". In there, there will be a big bold print title called "Custom User Title". Once you get to 500 post, this will appear and allow you to make a custom title.

[-Samantha-]

Thanks for this, guys:)