The quick way to check the wind forecast is at Seabreeze.
More detail at the coastal forecast provided by the Bureau of Meterology (BOM).
Less precise is Windguru
Tides are important too, easy is Willy Weather.
Wind forecasts change considerably and continually - this is the main issue going into any planned kitesurfing event. It is even possible that we may have no wind at all.
The best we can do to make wind happen is to chase it and to be flexible with the timetable - so we wait till the day before (typically the Thursday) before we make a call whether to go north or south from Sydney.
Then during the weekend itself we can drive to new locations if we think there's a chance of better wind.
There's lots of Murphy's Law or Sod's Law at play - and you'll find this is part of the kitesurfing experience. It's also an important part of the learning experience is reading the forecast and learning when to make a call to ditch that family BBQ and head to the beach.
There'll be lots of checking on the iPhone on the beach and at breakfast and before we go to bed and when we first wake-up - - and by your instructors in the days ahead of the weekend.