First of all, you need to apply for a job for the position of a character at a Disney theme park theatre. You can search the job by reading the job listings which are updated online on the website of that particular Disney Park.
For getting job as a character at Disney Park, you need to be a good actor. If you have no professional experience then make sure you have participated in school or college plays or drama clubs and know the basics of acting.
Disney characters entertain people with their acting and other performances on stage and you need to realise that talent and competency are the only skills which will help you to get your desired job.
Characters at a Disney park are usually those individuals who are extremely fit and also keep their bodies in shape. The reason is that they have to work for at least 8 hours a day or even more. So you have to be in good shape and your fitness level should also be good in order to cope up with the hectic routine at a Disney theatre.
Be confident during your job interview because confidence is the most important thing to become a character at a Disney theatre. Practice well before the interview as the employer can ask you for a demonstration during interview.
After getting the job, prepare yourself for spending many hours in training on a routine basis. They will never give you a chance to perform on stage until you are fully trained and ready.
Be fully prepared for facing worst conditions during training as sometimes it become very tough physically and many people quit saying that they cannot do it.
Dance is another important part for the characters at a Disney theatre. Make sure you know the basics of dance and work hard to master it during training. There are many roles that require dancing along with acting. So, be prepared for that.