On foot
The old city center can be easily explored on foot. To get between the upper and lower sections, take the Elevador Lacerda or the cable car, remember to take small change as the fare is just R$0.15. The streets between the two are considered dangerous even during the day.
By taxi
Salvador cab drivers must be competing with those in Rio for spots on Formula 1 racing teams. They will certainly get you where you're going quicker than the bus! However, as buses stop running after midnight, do be prepared to haggle quite a bit with taxistas who refuse to use the meter, especially if you've decided to explore far from your bed. Executive taxis white and blue don't have meters, and the prices are on a table, it's more expensive than city taxis, but they are much more comfortable, they are in stops in the main shopping malls, the airport, bus station, ferry-boat station and big hotels.
By bike
Cycling is not really a good option to get around in Salvador, as there aren't enough cycleways and parking for bicycles, and drivers don't have any respect for cyclists. An exception is the cycleway in the east coast of Salvador, which has 12,55 km and goes from Amaralina to Piatã beaches. Be aware that as the cycleway is not very used, a lot of pedestrians use it for walking.
By car
Renting a basic car with air conditioning 100+ kilometers or KM free costs R$ 110-140 per day, plus fuel. It's not hard to find your way accross Salvador avenues, but although people from Bahia have a reputation of being relaxed and easygoing, traffic is agressive somewhat like Rio de Janeiro, and you will frequently see drivers attempting dangerous overtakes on you. Pedestrians are also careless and unexpectely run to cross roads and streets. If you are not used to this type of traffic, consider asking for a private driver, which is possible on many car renting agencies. Renting a car may be a good idea if you plan to visit the beaches from the northern part of Bahia, with more time flexibility than allowed by travel agencies.
By bus
City buses, as in other Brazilian cities, are constant and confusing. Fares are normally R$2.80, as of June 2012, even for buses into the neighboring city of Lauro de Freitas. There is also the option of the air-conditioned executive buses for R$3. Remember to board in the back for the full-sized buses.
Know your landmarks and neighborhood names. Any large shopping area will have a complimentary frequented bus stop, and the major intercity terminal, Lapa, is next to Shopping Lapa.
Other major bus terminals include: Estação Iguatemi between the Rodoviaria and Shopping Iguatemi, and Estação Mussurunga located on the Paralela with buses usually connecting to Praia do Flamengo interior neighborhoods in Salvador.
If you are trying to make your way out of Pelourinho, you can either take the Elevador Lacerda down to the Comercio and find buses for just about every route, or walk to the Praca da Sé bus stop just south of the elevator, which has a much smaller selection of buses passing through, and many options of executive buses.
Buses are safe to ride at night, as long as you are on a frequented i.e. coastal route and dress/act inconspicuously. Service stops at midnight and begins again around 4:30-5AM. There are a limited number of lines that provide night service from midnight-4AM.
You can find more about about the Salvador bus routes and time tables one the website for the Superintendência de Transporte Público (http://www.stp.salvador.b...) in Portuguese only.