What should you expect with an expander? The bands are placed around the first molars, with an expansion appliance that goes across the roof of the mouth. Use the expander key, insert until it clicks into place and push towards the back of the mouth until the next hole comes up. The expander will have arrows pointing the direction for the expander key.
Useful tip: Best thing to do is lay really flat on the floor or a bed and have someone hold a flashlight for a better view.