A6 has a barre chord and a long stretch making it difficult to play at first. The index is first placed across the entire second fret, leaving the top joint just slightly hanging over. When you press down you want to be sure that all the strings are sounding, and none are dead. Next stretch your ring finger to the fourth fret of the C string and the pinky to the fourth fret of the A string. Keep the ring and pinky straight so they do not interfere with other strings either.