Like standard letter size paper, legal paper needs to be folded so that it can be mailed in a standard, legal-size envelope. Folding the legal paper the same way you fold letter-size paper, however, will result in a letter that will not fit into the envelope. This is because legal paper, measuring 8 1/2 inches by 14 inches, is longer than the 8 1/2 by 11-inch letter paper. The extra length makes folding the letter in a presentable manner different than you may be accustomed to if you normally use letter-size paper.
Lay the legal paper, printed side up, on a flat surface.
Fold the bottom edge of the paper upward, creasing it across, 5 inches from the bottom. Use a ruler to make sure that the crease is exactly 5 inches from the bottom edge. This will leave the top 4 inches of the paper exposed.
Fold the top 4 inches of the paper downward, creasing it where the bottom edge of the paper sits. This leaves you with a 5-inch by 8 1/2 inch folded letter.
Slip the folded letter into the envelope.