Just keep it simple. Hand massages, reading, pictures, walks, etc. I'm a memory impairment unit coordinator and the low functioning residents generally respond well to music. Be it a respite video, karaoke or sing-a-long -- it taps into early memories and it's as calming as it is joyful.
The residents also seem to enjoy balloon volleyball and respond well to round circle kicking. I place alarge-sized ball in the center of the circle, then push or gently kick the ball, and the residents kick the ball back to the center. I also play lively music in the background lead a multi-sensory activity.