Hold your non-dominant forearm horizontally across your body, to act like a surface or divider. Then take your dominant hand and form it into a fist, with your thumb sticking up. Starting from above your non-dominant forearm, move your dominant fist under your forearm, like a child playing hide-and-seek by hiding under a table.
We use the sign for under when we introduce toddlers and babies to the concept of relative location. We can do it through play dynamics such as hiding “under” the table.
Teach your child under when they are more adept at moving around. Incorporate this sign along with other location signs to help your child navigate their surroundings - and communicate with Mom or Dad - more easily.