Find out how much space is given. 2 or 3 panels worth? How big is each panel? How much horizontal (table space) available to show the things grown, the device made, or the equipment used?

What rules are there about what can't be displayed. They won't allow anything flammable, pathogenic, lasers, certain types of batteries, sharp objects, nasty chemicals,etc.

One can often still "show" the hazardous parts of the project via photographs or by filming the experiment and displaying the video on a computer screen.

A copy of the project report must be available at the display. A The project notebook with all thoughts and results neatly written up would be good, too.

The display also needs:A Title (in 96 point font or bigger). Don't use the word "Title" in the title!The hypothesis.A brief background to the issues addressed, or why this is an interesting problem. Sometimes a picture will explain the problem being addressed.

Pictures of the equipment used, especially if unusual.
Lots of pictures of the methodology of the experiment itself, and of the results.
In the display,try to use only the bare minimum text to communicate what basically happened. Use attractive images (graphs, photos and illustrations).

At the end of the display, a few words about what the next logical step / follow-on interesting experiment would be, based on the findings.