I'd say the most important thing is to have fun. It is honestly the best job in the world! It may seem difficult and challenging at first (like trying to learn AND then sign autographs with...well, um, limited appendages

) but it'll all be alright. I'll admit that the first 20 minutes I spent in costume I had serious doubts that I could do this for 4 whole months...but as it turns out I had the greatest time doing it and I cannot wait to get back down there to work again! So, just have fun and make the most of it! Pick up extra shifts, go to the entertainment workshops they have and don't be afraid to be outgoing in your costume (well, I suppose that's kinda character dependent, but still...). Best of luck!
ps: the character attendents are kind of like our "body guards" in a way...they are very protective of us and they've got our backs.