If memory serves you need to reach the rank of Muffin before you can give yourself a signature. Don't worry it won't take ya long, just make five posts on the forums and you'll be all set kid.
P.S. I'd suggest introducing yourself in the Welcoming Plaza , that should get you on your way.
My guess is that Zoey means it'd be part of the Team Rankings for users, just as there's an official Team Rank for Staff here (Alicorns and Royal Guards.) This would still fall under a special title or badge though, as Sugar Plum pointed out in their post.
I feel as though when it comes to an individual being motivated to contribute (or do) something it shouldn't be influenced by outside sources such as a special group or title, it should come from the pure will to do it for the users own benefit. I've found that while something such as this can motivate someone to contribute content, it's short lived and can actually do more harm than good.
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