Trees are a good start. Write down what you liked to do. Swing from the branches. Climb all the way to the top. Chew on bark, lol.
Seriously, don't worry about going in there and being "forced" to play. Trust me. It won't work. Tell T a flower told you that.
Did you ever play jump rope? Have a favorite song that went with it, like Miss Lulu had a steamboat?

A book?
You have to start small. Maybe you played games in the school yard, or passed notes in class. Or your favorite color crayon was robin's egg blue.
If anything comes to you, write it down, bring it in to T.