GBP/JPY is moving within corrective subwave B (colored magenta in the chart) that is part of impulse wave C of larger degree (colored royal blue in the chart). The former wave consists of A-B and C subwaves, subwave C is still developing - colored red in the chart. The targets of the upmove are Fibonacci retracements of 137.03-130.89, and expansions off 130.89-134.02-131.79.
Resistances:
- 133.72 = contracted objective point (COP)
- 133.96 = .50 retracement
- 134.68 = .618 ret
- 134.92 = objective point (OP)
If the price reverses down the immediate supports will be Fibonacci retracements of 122.49-139.93, and expansions off 139.93-132.90-137.03, 137.03-130.89-134.02.
Supports:
- 131.21 = .50 ret
- 130.23 = COP
- 130.00 = OP
- 129.15 = .618 ret
- 127.88 = OP

Overbought/Oversold
Assuming that the medium term trend is down but a correctiwe wave is under way it's preferable to stand aside until the correction is over or try long positions when the Detrended Oscillator gets below the zero level (10-15 pips below the current prices) or into the oversold area (35-50 pips below the current prices).
Read more on how to apply Fibonacci studies to calculate price targets.