What should I call myself on Xbox?

I can't decide what to call myself, I ask you for help

XX_masta_quickscopeZz_Xx

Best of all, none of the three things. It's just my opinion but come up with something better than something like that, a Gamertage is equivalent to a virtual first name. And none of these sound very appealing.

There are reasons why I generally avoid such people on Xbox.