Food!
Filipinos are passionate about their cuisine. Filipinos eat five meals a day, three large (breakfast, lunch, and dinner) and two little (breakfast, lunch, and dinner) (merienda or light snacks in between big meals). So bring a large appetite. If you want to get the full Filipino experience, you'll need to be willing to taste new and unusual foods, from cooked growing chick embryos to a scorching plate of chopped up pig's face. Don't be startled if a Filipino welcomes you with "have you eaten yet?" instead of "hi."
Also, you should savor a Philippine Mango, This may not save a life, but it will certainly improve one. Filipinos are justifiably proud of their bright yellow, delicious, and juicy national fruit. Eat a Philippine Mango whenever you get the chance since you won't find them like this anywhere else.