Being the $0 budget person that I am, I decided to make my own vent deflector for our bedroom because the stupid thing is right under the window, nowhere near the bed.
Here’s what I did
This is a cardboard carrier for a bulk purchase of juice boxes at Costco. It’s perfect because it is rigid. Use a steak knife to cut the corner off the box to fit over the vent.
You could use aluminum foil that you mold into deflector shape but that seems a bit flimsy to me.