First person begins with:
"I'm going on a trip with my baby and I'm bringing...some applesauce(or another "a" word).

The next person then would build the sentence with the next letter:
"I'm going on a trip with my baby and I'm bringing some applesauce and...a bottle(or another "b" word).

The game continues through the alphabet until all but one person has messed up. That person is the winner.