Sydney has an enormous number of places to drink and party. A limited number of venues have 24-hour licenses, however the majority close before 3AM and some as early as 11PM, particularly if there are nearby residents.
Busy venues will have door staff checking photo identification to determine that you are over 18. Admission is also commonly refused to those who seem visibly drunk. More popular venues have discriminatory door practices, the most common of which is refusing entry to groups of men who are not accompanied by women. Some pubs and most clubs will admit children accompanied by adults as long as they don't approach the bar or enter an area where there is gambling. Check with staff at the venue. Some pubs don't provide a nice environment for children some nights.
Many places have at least a basic dress code, enforced all hours in the city, and usually after 7pm in the suburbs. For most generic pubs, men should wear closed toe shoes not running sneakers, full-length pants, and a shirt with sleeves not a singlet. For clubs, men should don neat business-style shoes. In almost all cases, women can dress more freely, but a small number of places require closed shoes or dressy sandals or high heels.
Many pubs are called hotels, but only very few can ever offer you a place to sleep. Hotel pubs are usually found on a street corner with at least one ground-floor bar, and are usually a few floors high though not all floors may be open to the public.
Entry charges for live music or DJs are usual and range from $5 to $30 depending on clientèle. Entry charges are rare if you're going into a pub for a drink.
There is a taxi shift change at 3AM, and it is notoriously difficult to catch a taxi anywhere between 2:30AM and 3:30AM. Also beware that there is currently a government enforced lockout at many establishments between 2 and 5AM - which means that you need to stay inside or you won't be able to get back in - even if you go out for a cigarette smoking is illegal inside. Ask the bouncers or some locals if you're unsure and they will tell you which places are affected by the lockout and which aren't.
Some types of nightlife are concentrated in particular areas:
gay scene
Sydney's large gay scene is concentrated on Oxford Street in City East although it still has a large range of pubs and clubs for all ranges of sexuality and is a prominent nightspot for many party-goers. Sydney's queer community also can often be found on King Street in Newtown which offers a more relaxed place to gather and far fewer yobs.
students
Sydney's students drink in the Inner West. Try student bars Manning at Sydney Uni, the Roundhouse at UNSW and the Loft at UTS which all offer pleasant, hassle free environments, and noone checks if you're a student. Manning Bar is also great for a meal as they have their Manning BBQ. The Clare opposite UTS on Broadway, though very ratty looking, is a similarly popular place for students. There are many great bars and pubs on Broadway, such as the Lansdowne Hotel which also offers cheap lunch meals for $5-6 on some days of the week.
Sydney's microbreweries are in the Rocks and the City Centre.
There are many great nightclubs in Sydney, unfortunately they are very spread out so it would be a good idea to get an idea of were you want to go. Check guides in Friday's newspapers, or the free guides available in music stores and youth clothing stores.
tipping
Most bars and clubs in Sydney will simply return your change, and no tip is expected. Some more upmarket bars will return your change on a tray. Most Sydneysiders will simply collect the change from the tray, however feel free to leave the coins on the tray if you would like to tip. Working out a percentage of the drink cost, or tip per drink is never required.