About the C#maj7 chord
To play C# major 7th, use the first shape above. Use your index finger to barre the 1st fret across the G, C, and E strings. Place your ring finger on the 3rd fret of the A string. Strum all four strings and check that each one rings cleanly.
Root
C#
Quality
Major 7th
Notes
C# · E# · G# · B#
How the C#maj7 chord works
C#
Root(1)
The home note. It gives the chord its name.
E#
Major third(3)
The major-third interval that establishes the chord's major base.
G#
Perfect fifth(5)
Adds strength and stability.
B#
Major seventh(7)
Adds a major seventh above the root.