
First, ensure that your infant sleeps for the first 2 hours of the trip.
At that point you're almost halfway home, and all you had to do was keep your mouth SHUT to keep her from waking up.
Upon awakening, hand her an empty bottle to chew on & flirt with.

When the bottle loses its appeal and/or gets thrown around the car, try putting on Mommy's sunglasses.
Apparently, this is a sure-fire way to really aggravate your little one.
Caution: she may threaten or attempt to punch you.

And as things continue to go downhill, give her a bowl to hold as you attempt to fix dinner.
Nevermind the pureed orange blobs that fly everywhere as you tear off the top of the carrot container. Stay focused.
While your infant is screaming, spoon the soupy green "country vegetables" into her mouth, only to have her close her mouth and spit the green soup EVERYWHERE.
While you're frantically looking for a burp rag or washcloth to wipe everything up, the infant will enjoy sticking her fingers INTO her mouth of green soup and then onto MORE surfaces, such as her clothing and her fabric carseat.
Make sure this is all happening in the backseat while Daddy is totally oblivious in the front seat.

When the joy of one bowl runs out, try two.
She'll love to hit them together like cymbals.
Sure, it might be slightly annoying and loud, but hey-
you've gained another 5 mintues.
And that's worth it. :)