Kuala
Lumpur is a cosmopolitan city that is modern in all aspects, be it
fashion or technology. If you are visiting the city and thinking about
what to wear and how to dress in KL, then be at ease as you can wear
whatever you want to, till it is not offendable. The city is open to the
contemporary fashion and here people wear almost every type of clothing.
Considering that the city observes equatorial climate marked by high
levels of humidity, one should prefer wearing light cotton clothes to
escape the heat and sweat. For instance, clothes like t-shirts, short pants and bermudas are actually suitable in such climatic conditions. Rain showers are common in KL, so it's better to wear light clothes that can dry up easily. To shield yourself from the bright sun, prefer wearing cap and sunglasses. Also use enough of sunscreen lotion, whenever you're out. Since shopping malls, stores and restaurants are usually covered and air-conditioned; there you need not to worry about sunscreen or any other such thing.
While going to mosques, don't prefer wearing skimpy or revealing clothes because Muslims are against such practice. Though there is no particular dress code, it is advisable to dress decently so as to avoid any unwanted attention. Kuala Lumpur is an advanced city and how to dress is one's personal choice. It's better to dress modestly and look good, rather than appearing weird or stupid. To sum up, casual decent clothing, preferably in cotton, is best to be dressed in Kuala Lumpur.