About the C#sus2 chord
To play C# suspended 2nd, use the first shape above. Place your index finger on the 1st fret of the G string, your middle finger on the 3rd fret of the C string, your ring finger on the 4th fret of the E string, and your pinky finger on the 4th fret of the A string. Strum all four strings and check that each one rings cleanly.
Root
C#
Quality
Suspended 2nd
Notes
C# · D# · G#
How the C#sus2 chord works
C#
Root(1)
The home note. It gives the chord its name.
D#
Major second(2)
An open-sounding second that replaces the third.
G#
Perfect fifth(5)
Adds strength and stability.