It is impossible to use the present tense to talk about more than one action.
Here in this sentence we have two actions , one must be simple and the other must be continuous.
So you have to use the suitable tenses ( present , past , future ) .
Example: if Henry and Jimmy are using to do that every day so you can say ( Everyd Henry waches when Jimmy is smiling and tossing ,,,,,,,,, etc , we used present simple tense and present continuous tense.
But if they did it in the past so you have to say ( Henry watched Jimmy when Jimmy was smiling and tossing ,,,,, or you say Henry was watching when Jimmy smiled and tossed ,,,,, .