They say that babies need "tummy time" each day, a period of time where you place your baby on their belly and watch as they struggle to keep their head up. Eventually they learn to scoot about and then crawl.
She's top heavy. Her legs just sort of shoot out into the air, kicking and never finding the ground. So, much of her "tummy time" is spent with me laughing as she flails her limbs about in the air.