Mosquito Repellent, Singapore
Luggage and bags:
bring aloe vera for the bug bites, the sun burn and in my extreme case the heat rash. It is very expensive here and I am so mad at myself for forgetting to pack it.
Clothing/Shoes/Weather Gear: you can bring an umbrella but they are really cheap here, so you can stock up on some different designs because you will need them for a little almost every day.