AAC modeling is a critical communication partner strategy. Just like verbal communicators, individuals using AAC need to see other people using AAC. They need examples of how to use AAC in the ways that are expected, and they need to see that their way of communicating (using AAC) is a respected way of communicating (and that they are not the only person using AAC). Technically:

AAC modeling is the communication partner’s act of using AAC (touching words/phrases on an AAC system), while also talking to the individual.