It is considered rude to introduce yourself to strangers, it is generally advisable to ask some mutual acquaintance to introduce you. Strangers will speak with each other in the "formal" register of Urdu, and using the familiar register will be seen as very rude.
People of opposite sex do not shake hands when they greet each other. It is sometimes usual among men to put the left hand on your chest (heart) when shaking hands. In urban Sindh and in other parts of the country, men and women usually lower their head and lift their hand to their forehead to make the "adab" gesture when greeting each other.
When being introduced to elders or strangers while seated it is customary to get up as sign of respect.
It is advisable to ask a person how they wish to be addressed.