Compassion; being unafraid to admit that you’re not sure about something but being thorough enough to find follow-up with the right answer or referral, have fun with your client and their session; being a great teacher and a ferocious learner; enjoying what you do or find a different profession; staying current; have GREAT listening skills; being flexible in terms of your training approach, your communication style and your programming since after all, each client is an individual and deserves individual attention.
There are many, many more…
I agree with all previous posts. I would add:
1) A high level of honest and sincere communication skills (we deal with so many different people, in so many different environments, with little to no preparation. It really is good to know how to adapt your message and/or overall communication style on the fly, and still be able to develop fabulous rapport and connection).
2) Personal and professional integrity, respect, and ethics (kind of all the same thing, but still…). You have to present yourself in every situation in such a way that if somebody was watching you (and you didn’t know) you wouldn’t be embarrassed or immediately change the way you behaved.