The whole concept of the wallet-in-the-hip-pocket must be discarded while in Bali. Pickpockets know exactly how to get at them, and at purses and shoulderbags. Avoid zippered shoulder bags because the zipper doesn't always close all the way, leaving room for a hand to reach inside. Instead, use a latch or snap which fastens the bag and can be locked, or a bag with a small opening which you have to pry apart yourself. The less you open your bag in public, the better.
Snatch thieves work in pairs on a motorbike. One sitting in back grabbing your shoulder bag or moneybelt, dragging you with it if you don't let go, and the other driving. Be wary of approaching motorbikes. Some travelers bear scratch marks from thieves who try to tear off necklaces and watches. Don't put valuables in a camera case; thieves have caught on to this practice. Cheap styrofoam coolers are better for storing valuables because they don't look like they contain valuables.
When moving around the island, leave your address book, traveler's check serial numbers, passport number, photographs, heavy money, air tickets, and other hard-to-replace papers in the bottom of your backpack. You're less likely to lose your backpack, and valuables can be taken out in the privacy of your room as you need them. Your backpack offers the most security because it either remains in your room or on your back, making it difficult for a thief to get into it without being detected. Keep only those possessions you can live without in side pockets or on the top layer of unlocked rucksacks or daypacks.