The A Major 7th Chord is found by locating the 1, 3 , 5 and 7 positions (A, C#, E and G#) of the A Major Scale: A B C# D E F# G# A. The chord diagram chart below demonstrates how to play the AMaj7 Chord.
AMaj7 Chord Notes: A, C#, E and G#
Here is a key that will help you read the chart:
AMaj7 Guitar Chord Video
The video below will further demonstrate how to play this chord.