Jon chewed his lip thoughtfully for a moment, then the answer struck him.
"I wish that Sarah's wish had a time limit and from noon today everyone would start turning back to how they were before the wish and would be back to normal by tonight."
The two of them were compelled to look away, and when they looked back, everything seemed the same.
"It didn't work!" protested Sarah.
"Yes it did," replied Jon "we just have to wait. By tomorrow it'll all be over...I hope."
"So what now?" asked Sarah nervously.
"First," replied Jon, "I wish for there to be a time limit on your wish stopping me wanting the stone and that it expires in 5seconds." He turned to look at her thoughtfully. "Second, I wish that for the next week you would be compelled to act like me in the same fashion everyone is now acting like you, except it's an instant change not a gradual one. Third, to make life easier, while you're acting like me, all your stuff would change to be the sort of things I like." He smiled and stared at her "Maybe this will give you insight into what it's like to be me."
He turned away, looking at where Biff and a few other of the school jocks were playing volley ball and added "I'll make one concession for you. I wish while you're acting like me, you'll still be dating Biff and by doing so, he'll become a more empathetic person by the end of your 'punishment'."
He turned back at her and smiled, knowing that his distaste for the personality that Sarah had imposed on everyone would prevent the Jon-ised Sarah from trying to circumvent the wish and return to her queen bitch personality.