Hi John,
All good Qs. Firstly normally we try to plan to avoid a full moon. You are in Sydney so far more likely to get clear skies then us here in Melbourne
S
Secondly, each person normally decides beforehand what targets they wish to see/image. If you are doing visual, it is a lot quicker to set up (well, hopefully!) so can do more targets. There are plenty of methods to help you choose - if you are new, try going for the 'classics' which are bright and easy to spot. Once you feel comfortable navigating the night sky (goto, or hopping) then you can try the more faint fuzzy stuff.
To choose what to see there are a few lists on IIS (for example, galaxies listed by brightness). I find using a planetarium software very very useful as you can punch in your location and most can generate a list of 'best targets'. I personally like going through the Messier catalogue first as they are relatively easy to see and have lots of literature for you to read up on. As the weather conditions can change I would say for a variety - galaxies, nebulas, clusters etc. This way if the seeing is bad or things aren't shaping up, you have come prepared with backup options and not waste valuable dark sky time with looking at a computer screen worrying what to look at.
Just go to a few sessions and you will eventually work out a routine that works best for you!