The crab is considered by Carney to be one of the most precise of the patterns, providing reversals in extremely close proximity to what the Fibonacci numbers indicate.
In a bullish pattern, point B will pullback 0.382 to 0.618 of XA. BC will retrace 0.382 to 0.886 of AB. CD extends 2.618 to 3.618 of AB. Point D is a 1.618 extension of XA. Take longs near D, with a stop loss not far below.