Create a poster featuring the presidential bust---head and shoulders---with the bust filling the entire poster. This graphic art should be set at very low opacity, at 20 percent or less, to a point where it is almost a watermark, or ghost image. But, keep the image recognizable, if very light, and surround the president's head with the information you wish to present. You can include a small, fine-detail photograph on the poster, to be seen when a viewer stands in front of the poster to read all the details.
Create a poster to look like giant money, either a single bill of currency or a large, shiny coin. The entire poster can be the bill, and you can insert any president's face into the "presidential cameo." Change the denomination of the bill to represent the number of the president. In close, where the fine print goes on currency, instead place the pertinent information you wish to confer, or place "pop-up" bubbles around that are screened white versions of the underlying graphic so that viewers can read the text.
Study various samples of postage stamp art, and create your own giant version of a postage stamp, featuring the president you are highlighting. The White House can be the stamp's subject, or the stamp can depict a series of presidents. Or, you can create a series of large postage-stamp posters to depict 10 to 15 presidents.
On all posters, it is important to include details about the president's life and term. Consider including information such as the president's years in office, number of terms, vice president, dates of birth and death, wife's name and other interesting information such as the president's claim to fame as commander in chief.