In addition to asking for more, babies also need to be able to signal being finished. Using the sign for the phrase all done helps parents and preverbal babies communicate, especially during mealtime.
Teach your baby the sign for the word more in baby sign language with the following description and video. Use your dominant hand to form the signs.
Baby sign language, baby sign, or baby signing is used by hearing parents with pre-verbal hearing children to improve communication. My baby signs are based on ASL (American Sign Language) signs. Baby signing is distinct from sign language.
All Done
Hold the hands in front of the chest with the palms facing up and the pinkies touching. Pull the hands while rotating the hands to make the palms face down.
References
Beyer, Monica. 2006. Baby talk: A guide to using basic sign language to communicate with your baby. New York: Jeremy P. Tarcher/Penguin.