Wow he/she is really cute, such big eyes!
Don't know much about fat tailed geckos but i guess they're similar to leo's, here's some general advice til someone more knowledgable comes along.
Make sure his/her food is the right size for him/her so it can be digested properly. Maintain viv at correct temps for a fat tail and don't handle until the lizard is settled in the new environment.
You might get more responses if you post your own thread as people will be looking at leo morphs in this one.
Hope that helps xXx