Although the judges' score sheets may not show many points deducted for those things, a paper with several mechanical errors may create a negative feeling about the whole paper. Pay attention to transitional words and sentences, those words and sentences necessary to get from one idea to another. Everything in the paper must hang together. Words you choose must be very precise. They must say exactly what you mean.
Exhibits are primarily visual.
The display itself must tell the story. There should be a point of focus that draws the observer into the exhibit. Don't put so much in the display that confusion results. The eye should be drawn easily from one idea to another until the entire story becomes clear. Use the allotted space in creative ways.