Inform your
credit card company about your travel. Try to use one of your cards throughout. If possible when your return ask for a new card with a new number on it. Make sure you have intn'l roaming in case your bank wants to contact you when you use the credit card in Malaysia.
KL airport is away from the city. It is also a big airport. Keep sufficient time to reach city and back to airport.
In shopping malls esp on electronic goods, you can bargain to some extent. Do a price comparison across different shops as each mall will have many shops carrying the same product.
Do not entertain any conversation if anyone approaches you to swap their currency for Indian money saying they are travelling to india shortly and would like to take Indian currency with them. Direct them to money changer that will be quite common in malls. In crowded places esp touristy spots, exercise caution with your belongings.
You can take a city tour that may cover their palace, twin tower, etc. You can also visit Batu caves, it has a Hindu temple. If you have time try Sunway lagoon. Expensive to stay but it has a decent theme park, mall and a water sport area. You can spend a day there. You can visit Genting highlands (2 to 3 hrs from KL) if you want to try the casino. The theme park is not that good.
In small eateries, you will see Tosai in their menu. It is our Dosa
🙂 If you are conversant in Tamil, you will feel at home in Indian localities.