Take several photographs that relate to the movie's plot, but don't reveal it. For example, if the movie contains an assassination scene, don't take a picture of the assassination event itself. Instead, take a picture of the gun behind the assassin's back, or of a shadowy silhouette lurking behind the victim.
Upload the photographs to a computer and choose one that you think is the most captivating. Most movie posters feature one, large photograph rather than many different photographs. Pick a photograph that has enough unimportant areas that can be covered with text.
Copy or import the photo file into a graphic software program such as PowerPoint or Indesign. Enlarge the photo by dragging it outward from one corner while holding down the shift key. This will ensure that it increases its size proportionally. Enlarge the photo so it extends to the edges, filling the entire page template.
Add text to your photograph. Do not obscure important parts of the photograph such as faces. Use a text color that contrasts with the photograph. For example, if the text runs across a dark portion of the photograph, use white text. Include the movie title in large font across the top, middle or bottom of the poster. Include the names of the movie's stars and its director, as well as the film's website in slightly smaller font. To further captivate the poster viewer, include an enticing tag line or a quote from the movie. Finally, include the movie credits at the bottom of the poster in very small font.
Save the file onto a flash drive and take it to a print shop that has large, poster-sized printing equipment. Print the poster with assistance from the print shop staff. According to Cinema Masterpieces, typical movie poster size in the U.S. is 27 inches by 40 inches.