1. Starting position: Your dominant hand is open, palm facing inward, with your fingers spread.
2. Movement: Bring your hand inward, toward your chest, as if you are pushing something into a space.
3. Ending position: Your hand ends up near your chest, palm facing inwards.
Visual Representation: Imagine you are pushing a small object into a box that's held close to your chest.
Important Note: The sign for "in" can be modified to show different meanings depending on the context. For example, it can be used to sign "inside" or "within."