Determine which method your sign or marquee display uses to fasten its letters. Decide whether your sign uses slotted, snap-lock, tab, aluminum or flex-plastic lettering by examining your sign or the specifications that came with it.
Insert the key into the sign keyhole, if required, and open the case. Ensure that the existing letters won't fall or blow away in the wind by keeping part of the case closed as you work to remove them. If using a letter changer pole (typically 18 feet extendable), rotate the handle in a counterclockwise fashion to loosen the pole release mechanism. Extend the pole to the desired height and tighten the handle in a clockwise fashion until the pole is secure. Attach the individual letters to the suction cup or hook at the end of the pole for removing and reapplying (not applicable for flex-plastic letters).
Place new letters on the "row" by either snapping, hinging or bending them in place, depending on your specific marquee sign. For example, for snap-lock signs, grab the top of each letter you wish to rearrange and lift it straight up from the holding mechanism. Keep in mind the correct direction, spelling and punctuation of the words as you work.
Step back from the sign to ensure the message is exactly to your specifications and the desired distance between words has been met.
Make sure the lettering is securely fastened, and close and lock the case.