As you know, science fair projects are displayed on display boards.
Take in account that a lot depends on a good display board. If your display board is attractive, the visitors (including the judges) will have good impression about it. However, if your display board is cluttered and in a mess, the readers will get a bad impression about your work and will ignore it, no matter how worthy is your research.
Your display should be a promotional presentation and not a full description of your project. Remember, the judges and readers have only a few minutes at their disposal to get impressed by your project.
A general display board layout follows. There are possible other variations for the organization of your science fair project on the display board.