Understand
Chittagong is a fairly big, spread out town, and the largest international seaport in the country. Like Dhaka the streets are filled with masses of rickshaws, though the city puts in a little more effort to keep its streets and sidewalks clean. Foreigners will notice a distinct increase in nuisance from beggars in certain intersections, for example, New Market Circle and the central Railway Station. Majority of the beggars are from other parts of the country such as Greater Mymensingh Region and Greater Noakhali area. This is due to the fact that Chittagonian people are more prone to charity relative to other parts of the country.
The busiest part of town is the area around the train station and Station Road, while things get a little more bearable as you move further north. GEC Circle is the intersection of Zakir Hossain Rd, O. R. Nizam Rd and CDA Avenue, about 3 km north of the train station, and is the center of middle to upper class life with a variety of shady restaurants and shopping.
Chittagong is a conservative place. Local women tend to dress in modest clothing and don't like to shake hands with men. This does not apply to the upper class who are very westernised. Local people aren't offended when foreigners don't comply with the expectations of local people. Foreigners drinking alcohol or foreign women wearing skirts which show their bare legs are going to upset people. If you are going to do that there will be no end to males staring at you.
In the more affluent neighborhoods like Khulshi and Nasirabad local women are more westernised. The parties that let women have fun are mostly indoors, and Chittagong Club or Hotel Agrabad are fairly happening places at that.
The Chittagonian enthusiasm for inviting people to massive feasts is a bit of legend both locally and elsewhere in Bangladesh. Known as mezbani these feasts feature a tremendously hot curry, usually of beef. If you're not used to it, approach with caution.