Miscellaneous: Go to the park in October! The crowds are very small, our longest wait was 45 minutes which is great compared to the 3+ hours in the summer. Wear warm cloths with layers, get a locker when you get there for your coat and stuff and then when the sun goes down go back for it. Take gloves and a hat! It's chilly but I'd rather be chilly than sweating in 100 degree weather while waiting in 3 hour lines. Also, the park does it all up in Halloween...very cool.
Luggage and bags: You certainly don't want to be without your bathing suit at this place. Sandals or flip flops are a must when on the water rides. The park people don't like you in bare feet! But make sure you have running shoes for the rest of the day, you will need a comfortable pair of shoes. You are always walking somewhere.
Clothing/Shoes/Weather Gear: Don't forget a towel, when it comes time to dry up and change back into the street clothes after being on the water rides you will need this item!
Toiletries and Medical Supplies: The park has a medical service. Thank goodness we have never had to use it.
Photo Equipment: Make sure to pack lots of film. You can buy it at the park but it will cost ya a little more for the convience!
Clothing/Shoes/Weather Gear: If you are going to Cedar Point, you might want to bring a change of clothes and shoes to the park in case you get soaked on one of the water rides. Maybe a poncho or something because it seems to rain there a lot.
Toiletries and Medical Supplies: Sunscreen and sunglasses.