How much tummy time

by Danielle Pense
(W.A.)

As a first time mum I was wondering how much Tummy Time should my child have? My child is 4 weeks old and was 4 weeks premature. How much of the time he is awake should be spent doing tummy time? Is there any affect of doing tummy time on his sleep pattern? Obviously we'd like to have a good night's sleep.