If you want to observe the Transit of Venus then the first thing to do is organise an observing site. The Transit as viewed from Sydney will start at 8:16am with the Sun at an elevation of 13 degrees in the North Eastern sky and ends at 2:44pm with the Sun at 20 degrees in the North Western sky. If you want to observe the beginning of the Transit then the altitude of 13 degrees is quite low and you will need a North Eastern Horizon that is low and clear of obstructions. Within the environs of Sydney you will need to locate a high point with a clear North Eastern horizon or go to a coastal area. Similarly for the end of the Transit in the Western sky, where one option is to have two observing sites to travel between, there's plenty of time to travel, about 5 hours.
The directions in azimuth for Sydney will be approximately 50 degrees at the beginning at 320 degrees at the end, when you start to select a viewing site try mapping out these lines to get a feel for where you need to be on the day.