AUD/USD is moving within corrective subwave B (colored magenta in the chart) that is part of impulse wave C of medium term uptrend - colored royal blue in the chart. The targets of the downmove are Fibonacci retracements of 1.0442-1.0775.
Supports:
- 1.0648 = .382 retracement
- 1.0608 = .50 ret
- 1.0569 = .618 ret
If the uptrend resumes and the price breaks above 1.0775 the immediate resistances will be Fibonacci expansions off 0.9709-1.0580-1.0389, 1.0389-1.0578-1.0442.
Resistances:
- 1.0927-37 = confluence area of COP and SXOP

Overbought/Oversold
Assuming that the medium term trend is up and current wave is corrective it's preferable to stand aside or try shorts when the Detrended Oscillator goes above the zero level (25-30 pips above the current prices) or gets into the overbought area (50-60 pips above the current prices).
Read more on how to apply Fibonacci studies to calculate price targets.