Getting there: Macao has an international airport, and it can be reached by bus and ferry from Hong Kong and Zhuhai in the mainland.
The ferry from Hong Kong takes one hour and departures are frequent from Kowloon and Central. Direct buses using the bridge are supposed to start in the next few months, although they will be run by casinos, so you will have to take public transport or a taxi to reach tourist sites. The ferry is always busy on the return journey, so make sure you have a confirmed departure time, or you will have to wait.
Getting around: Public buses are plentiful and easy to use. A single trip costs six patacas, although drivers will accept the same amount in Hong Kong dollars. Just drop the money into the box near the driver.