Article in English: The best way to deal with bottle cleaning when travelling is to be prepared.  Carry a small bottle of dish soap and a bottle brush in a sealable plastic bag at all times. Use disposable bottle liners, so you only have to bring one bottle. The liners can be changed after each feed so the bottle only needs to be washed at night. If you're staying somewhere with a microwave, bring a portable microwave sterilizer with you when you travel. If you're prepared and have your dish soap and bottle brush with you, you can wash the bottles in any available sink.  Just make sure to give the sink a rinse down first, to remove any obvious dirt. Once washed, place the bottle parts on a clean towel to dry. If you've used a sink with water unsafe for drinking, you may need to sterilize bottles while traveling.  As mentioned above, the easiest way to do this is with a portable microwave sterilizer, but if you don't have access to a microwave, you can make do with a travel kettle and a small pair of bottle tongs. Simply fill the kettle with water, plug it in and allow to boil. Pour the boiling water over the (washed) bottle parts in the sink. Use the tongs to remove the items from the sink and place them on a clean towel to dry.

Summary in Indonesian:
Bersiaplah. Cuci botol tersebut dalam bak cuci hotel atau bak dapur umum. Sterilkan dengan menggunakan ketel perjalanan.