I'm real curious about this, and I can't find it under my profile settings.
On FunAdvice? You don't.
Any accounts that are made after the site upgrade a couple of years ago are automatically put into a numbering system, as opposed to names. You can't change it.
I use to know.. Before i took an arrow to the knee..
And Before they updated the site to the gayness it is now..
That sucks....but better than my old name.