Unless motion is designated by an arrow, showing the hand position depicted in an alphabet chart for sign language is the only step to signing the letter. Finger-spelling, signing out a word letter-by-letter instead of showing the word's unique sign, is used when a signer does not know the unique sign to a word or no such hand sign exists.
The letters J and Z are the only signs in the alphabet that require movement. Hand signs are shown with deliberate motion so that the sign and the transition between signs do not appear muddled. Hands are held up about shoulder height and must not cover the face as facial expressions are critical to communicating emotion, similar to tone and inflection in spoken language.
When performing a hand sign with motion, start the sign at shoulder height like normal; and, then follow the direction of the arrow on the diagram. Some signs, such as the letters J and Z, do not change the hand's shape as they move through space. Other signs have different starting and ending hand positions that coincide with the motion. For example, the sign for "sleep" begins with an open hand to partially cover the face and ends with a closed hand at the chin.