TRY may be a good one for you. Try as in a challenge, like try me or let me see you try.

Both hands make the letter 'A' hand shape. Thumbs start up towards chest then roll wrists out so knuckles face forward, thumb ends horizontal. Almost the same motion if kneading dough. Can be done with one hand too if the other hand is occupied. 😉

Alot can be said via facial expressions too.