I tied green balloons to a long piece of yarn an topped it of with a red balloon for the caterpillar's head to drape over the mirror. I also made the happy birthday bunting with green and yellow construction paper and threaded yarn through holes I made with a hole puncher. My best advice for the bunting is to use a pattern to cut out the flags - do not try to free-hand it. Cut equal rectangles for the letters so they're all the same size.
My only regret is that I didn't buy enough beer. I had plenty of hard liquor left but ran out of beer early. Other than that, the party was a huge hit!