In general, Indonesians are very laidback however, there are some do's and don'ts you should be aware of when in Jakarta. Whenever you're visiting a mosque, temple, and even some shops, make sure to remove your shoes before entrance. When you're in town, dress conservatively in clothes shorts and skirts that cover your knees.
If you're travelling in Jakarta with your partner or any local, be sure to refrain from showing any act of affection such as hugging and kissing as its considered somewhat disrespectful. Keep your temper in check, even in a difficult situation.