Modeling means you using the AAC system to talk to the AAC user.  We point to the words or press words on the AAC system as we speak. Do this without expecting a response from the AAC user.  If you think about it, this is exactly the same way that all children learn spoken language. We “model” or talk to them all day, every day, and over time most of them learn to talk by listening to our models. AAC works the same way. We need to talk with them using the device for several hours, days, months, and years before they will begin to use the device on their own. It is okay if the AAC user is not pressing buttons; keep modeling and their skills will build.