Cholera and smallpox vaccination is required for travelers entering Malaysia. Yellow fever vaccination is required for arrivals from infected areas and from yellow fever endemics zones except for children under one. Some areas of Malaysia do have malaria so it's a good idea to keep this in mind before you visit. Dengue fever is another mosquito born illness that is prevalent in most parts of Southeast Asia. The only way to avoid contacting the disease is to protect yourself against mosquito bites as best as possible.
Most Malaysians are devout Muslims and Islam itself provides the social fabric of the country. Therefore it is advised that unless traveling in the main centers respectful attire should be worn, especially by women. You should not expose too much flesh. Cover your shoulders and avoid wearing high-cut shorts or skirts.
Light, cool, and casual clothing is recommended all year round.
Do not carry drugs to Malaysia. Malaysia has very strict laws against drug trafficking. Partaking in the use of or distribution of drugs in Malaysia carries a mandatory death penalty.
The seas around Malaysia are generally clear and warm. Make sure you put sun cream on and wear a hat and sunglasses when venturing onto the beach. It is also suggested for those with particularly fair skin, to wear some form of protective clothing even when swimming. Topless bathing is totally out of the question.
The country runs on a normal eight hours a day system with Saturday as half day and Sunday as the rest day. In the states of Kelantan, Terengganu, and Kedah, Friday is the rest day with Thursday as half days. Departmental Stores and supermarkets are open daily from 10 a.m. to 10 p.m.