A lot of fun can be had in getting other people to do silly things! You can play a simple version of, ‘Simon Says’, and include actions that your child can either join in with or finds funny!
You can use symbols in the playground. Just the simple “more” and “stop” from a Core Vocabulary chart could be useful. The turn-taking chart also works well in the playground or in the garden with outdoor toys.
If you have the correct software (Boardmaker, Communicate in Print or Symbolmate) you can download editable versions of these here.