Do a contrat and compare on your idea of the perfect girl as compared to your current girl.
My idea of a perfect woman would start with looks. Many people believe that looks are not important, but unfortunately that is what initially attracts two people. The perfect woman for me would have silken blonde hair, gently cascading over her shoulders and nestling in the small of her back. Her brilliant blue eyes would pierce you to your very soul and grip you in their angelic gaze. Her pouty, crimsion lips would hold everyone's attention as she as she slowly mouths "I love you, Craig." She would have the body of a supermodel, and the graceful finesse of a jungle cat.... Move on to include her personality, how she enjoys the same things as you, and how she would remember to buy a gift for your mothers birthday for you. Now, contrast and compare her to your current girlfriend.
While visiting my uncle in BFE, Lousiana last summer I met my current girlfriend. Most people around those parts considered her to be very attractive. She has this bright orange hair, which is matted and unkempt resembling an unwound spool of copper wire. She has pasty-white skin, and a body resembling Frosty the Snowman-- on a warm day. The thing that will always last in my memory is her face. She has these urine yellow eyes that reflect the liveliness and intelligence of a basset hound. Most of her teeth are chipped and broken off at the gumline. You should see her smile! Oh, God, she has so many freckles. It looks as if she was standing in front of a screen door when someone slung feces at it. *FWAPP*.... Continue on about her poor hygene, surly attitude, etc. Please feel free to use any and/or all of what I've written for your paper. Good luck!
Or you could always go with the Mustang thing.