If you are already observing the children's likes, dislikes, interests etc then it is a very small step forward to think about how you can enhance their enjoyment and play by providing resources and play opportunities to build on what they are doing now and move them forwards.
You probably do it already without realising...
You see a child really interested in role play and remember some appropriate hats / other resources / dressing up clothes that he might enjoy and find them for next session...
You are keeping to the principles of playwork by enhancing children's play without interfering and you are following the Eyfs by showing how you plan for the next steps in children's learning and development.
Hth
