Here’s how it works:

Person 1 makes a wish
Person 2 grants it, with a hilariously unpleasant twist, then makes a wish of his/her own.
The next person then corrupts THAT wish, and makes his own wish, and so on.

Like so:

Person 1: I wish I had a Maserati.

Person 2: Your wish is granted! You have a Maserati. By Matchbox.
I wish I could fly.

Person 3: Your wish is granted! You can fly! You just can’t land.
I wish every day was Christmas Eve.

Person 4:
Your wish is granted! Every day IS Christmas Eve–and you’re in retail.

I’ll go first.

I wish I was on vacation.
(play in comments section)