First verse - go down the stairs and out into the audience. Find a different woman to say every line to. Offer each woman your hand. Some will take it, some won’t. “Perfect” metaphor for young love.
(interlude before Parlo d’amore vegliando, go back up to the stage, lie on the bed and face the audience)
At repetition of “Parlo d’amore vegliando” start chasing Susanna around the stage. At ‘venti’, Cherubino has to corner Susanna right on top of the bed.
Every line, Cherubino moves a little farther forward, and Susanna inches a little further back until it looks like Cherubino is right over her on the bed.
Right before the last “Parlo d’amor con me!”, Cherubino gives Susanna a peck on the cheek, and leaps up off the bed.
That is the whole staging.