If your mind is not on your money, you'll be vulnerable to pickpockets. Don't put your wallet in your back pocket-instead keep money deep inside your front trouser pockets. Be wary of minor accidents-being shoved or bumped, or having your foot stepped on. Don't be taken in by distractions, and be very watchful while attending crowded festivals. One big advantage of traveling with someone is that you're less likely to get robbed; you can keep an eye on each other and your gear.
As a general rule, don't let anyone touch you. On Kuta don't let the kids selling bracelets, wrist bands, or watches near you. They might try to pick your pocket, moneybelt, or fanny pack-working in tandem, one shows you the wares while the another shows you how a moneybelt "works" by putting it around you, holding the belt just above your wallet. No matter how cute or friendly they appear, just walk around them. If it's your first time in Asia, it's always better to buy in a shop and not from street peddlers.
Be cautious on Bali's bemo where travelers get ripped off by young pickpockets dressed as schoolkids. Working in groups, one or two act as a diversion while an accomplice steals. A large package, basket, or painting serves as cover. On the bemo which ply the tourist corridor between the capital and the hinterland, don't freak out if a pickpocket probes your jeans or shoulder bag for money. Take the strange fingers out, point, and announce to everyone, "Pencopet!" ("Pickpocket!").
Probably no one will do anything, but the thief won't stick around after that. Sit in the "traveler's seat" in the back of the bemo with your right or left side next to the cab. This will make your pockets and bags more difficult to get into. Keep your backpack against the cab with your eye on it, pockets facing the wall. If you see a suspicious situation shaping up, just get out and flag down another bemo-why take chances?