If your baby is resistant to spending time on his tum-tum, use these tips to make it more fun:
Get on your tummy, too! Lie down on the floor facing your little one and sing songs, make silly faces, and chat. Offer him a toy with a plastic mirror so he can gaze at himself.
Tempt him to reach out. Scatter some of his favorite toys on the floor around him, or invest in a play mat with fun activities to keep him entertained in a face-down position.
Be the mat. Place your tiny tot on your stomach for some heart-to-heart bonding time. My Nathan also loved to play "Rocket Ship" (only for babies with neck control). I'd lie down on my back and bring my knees up to my chest, like an abdominal crunch, then place him on my shins, facing me. Holding him by his arms, I'd slowly rock my legs up and down, saying "Blast off!"
Set him free. Take him out of the swing, bouncy seat, or stroller and allow plenty of opportunity for physical play to flex all of his growing muscles.