Even before your baby is mobile he can enjoy playing with a ball. As soon as he is able to sit independently, encourage him to roll the ball to you and you back to him.
This can be played with friends to encourage recognition of friends names or why not with favourite soft toys in a ring, although you will need to do a bit more rolling! Invent your own song as you go.
‘I roll the ball to Dora, she rolls it back to me, roll the ball, roll the ball, roll it back to me.’
Once they are on the move, the ball can be kicked, passed or thrown.