None of what follows is to be taken as criticism of Azerbaijan or the Azerbaijani people. After 70 years of Soviet rule, they are striving hard to bring their country into the 20th Century, and prepare it for the 21st - and succeeding. However, in many ways, the infrastructure is not yet up to world standards, and as a foreign visitor you need to be prepared for this.
English is not widely spoken.
You should carry your passport with you at all times when you are on the street. Local people are required to do this, and if you do, it will make life easier for you in the event that you are stopped by the police.
Azerbaijan has suffered several coup attempts in recent years, and has also suffered a bloody war over Nagorno Karabakh. Understandably, comments or jokes about political affairs are not likely to be well received, and it is better to avoid these subjects altogether.
If you travel by metro, you may have to walk a fair distance from the station to your final destination.
A year or so ago, there was a terrorist bombing on the metro. As a result, people are very security conscious; there are guards at the metro stations, and if you are carrying any kind of bag, they may ask to search it. This is normal, and should not be a cause for concern.
In October 1995, an horrific accident on the metro killed more than 300 people in a fire.
It is also possible to flag down any passing car on the street, and ask if they will take you to wherever you want to get to. (Obviously, you need to speak the language, for this to work). Agree a price before you get in.
You can walk the streets safely by day in most places. After dark, more caution is needed. Ladies should generally not go around on their own after dark, and should avoid taking taxis on their own at any time.
If you are recognised as a foreigner, you may be stopped and questioned by the police. On one trip, I was standing outside Baku Sovieti metro, and the police hauled me (and two friends) inside, searched us and questioned us. They were polite, and there was no physical violence. Nonetheless, this was a slightly un- nerving experience. If it happens to you, stay calm; whatever you do, do not let yourself get angry, and do not resort to any kind of threats or abuse. Be patient. I was only kept a few minutes; someone else I knew was detained for several hours before being released.
Almost everyone has minor health problems in Baku (upset stomachs, fevers etc). It is worth taking a basic health kit (Tylenol / Paracetamol, Imodium, plasters, antiseptic cream) with you.
It is not recommended to drink tap water unless it has been filtered or boiled. This is the main transport mechanism for bugs. In recent years, there have been outbreaks of cholera in the former Soviet Union, including the north Caucasus area.
Similarly, raw fruit and vegetables are to be regarded as suspect.
Things which are (usually) safe to eat: Most things which have recently been cooked, bread, meat, soup, ice cream, candy cars, drinks which come in cartons or foil packs (from Iran), anything which is pre-packed.
There is a growing number of Turkish restuarants and kebab shops in the city center. These are generally good places to eat. If you hanker for something a bit "westernised", try the recently opened "Rapsodi" restuarant on Fountain Square.
I recently discovered a good clean Indian restuarant, about 50 yards along from the 26 Commissars monument towards the Palace of Government. (26 Commissars monument is just across from Sahil metro). I ate there a couple of times without getting ill, and enjoyed the meal both times. The veggie Samosas are particularly good.