Firstly it must be clear in our minds that a fancy dress theme means to enjoy and participate. At pre school level one is allowed to watch the child but schools generally conduct it in their classes. The clothes that are made or hired must have the comfort quotient always high. The child must be educated how to handle the props or use the crown or any head gear. Teachers and helpers take adequate care and so the child is able to present himself in the same decorum.
For a hired dress the child must be comfortable with the size. Do not adjust the size forcibly as this is sloppy and may come off or seem uncomfortable on the stage. Ask the shop if any kind of altering is allowed and proceed for the same. The shops charge a rate and also ask for a stipulated time delivery schedule. Caring for the hired clothes is surely a responsibility.
The fancy dresses come in as angel fancy dress or a cartoon character. Whatever you decide it’s important to make the child rehearse the walk, hold the props, use the make up and recite the dialogues. One must rehearse in a professional way as any kind of joke will be picked up by the child in the same manner. In case you are dressing the child as a penguin or a sea horse then first let them know the names of other sea creatures. Show them pictures of the same in magazines and slowly let them learn the words.
Make dialogues which are easy to understand and yet allow them to pronounce clearly. In case you include a difficult word then split the same phonetically so that they learn the break up well. Earlier let them just run through the dialogues and slowly get the act with expressions and hand gestures. All children are born actors and they love to mimic you. Hence our act has to be perfect and the preparation has to be done well. Certainly do not goad your child to do something forcibly. Give them time and persuade them.