1.Do not chew gum,which is banned in singapore and may get you arrested. leave it at home before you travel .2.Do not smoke in public. smoking is illegal in enclosed public place.3.Do not discuss religion or politics.do not make jokes about them either. 4.Do not point at someone with your index finger, which is considered very rude.5.Do not tip. tipping is not customary in Singapore and it's even frowned upon by the government.