After the first wing is complete, the price goes down again, to a level close to the lower corner of the first "wing". The price doesn’t actually have to reach the exact same mark as in the first wing. The angle of the second wing may be slightly higher or lower. Visually, it forms a second triangle adjacent to the first one. The subsequent bounce continues until the price rises higher than the point of convergence of the two "wings". After that, the pattern is formed.
In a standard Gartley Butterfly, the distance from A to B is approximately the same as the distance from C to D. In harmonic patterns, this principle is known as "AB=CD". In this case, if you draw segments between AB and CD, they may turn out almost parallel.
The first point is designated as "X". If the segment drawn from X to A goes from bottom to top, and from C to D – from top to bottom, such a butterfly is regarded as bullish. After its formation, the price of the instrument is expected to rise. If the beam from X to A passes from top to bottom, and then C to D from bottom to top, then it’s a bearish butterfly portending a price drop.