Though Malaysians don't expect from foreigners to follow the same clothing conduct which they observe, it is always better to dress decently to keep away from confrontation. Beachwear is acceptable on beaches, but you mustn't roam away from the beach in such costume. Topless sunbathing is absolutely a big 'No'. When meandering through city streets, try not wearing too short clothes and prefer keeping your shoulders covered.
Women should not prefer wearing short skirts, sleeveless and tiny tops or very skimpy clothes, but try something
modest like t-shirts, knee
length skirts, singlets with thick straps. When visiting mosques, it's
advisable for women to cover their heads and wear decent clothes.
Considering the climatic conditions of Malaysia, wear comfortable
clothes like t-shirts, pants, jeans, three-fourths, tunics, long skirts,
tank tops, khaki shorts etc. Bring a pair of slip on footwear because while visiting religious places and homes, you have to take out your footwear. Casual and cool clothing is totally acceptable in the country, but not revealing at any cost. While visiting any government offices, make sure to dress formally since casual dress is considered as impertinent. Nobody would knock you down for this, but it's good to be respectful to others' culture. In short and snappy terms, casual and decent clothing is suggested for Malaysia round the year.