If you are unsure if you have a sleep disorder or not, you need to know for sure so you can come to terms with it. You need to know the things that you can and cannot do to be sure. You need to bring items with you that are prescribed by your doctor. You also need to bring clothes that you know you would be able to sleep in easily. Do not try to take naps before your study so that you can sleep better.
It will be best if you can avoid any food or beverage that contains caffeine hours before your study takes place as it can make you stay up for a longer period of time. Do let the people know if you have special needs so that they can address these needs easily.