About the Bbsus4 chord
To play Bb suspended 4th, use the first shape above. Use your index finger to barre the 1st fret across the E and A strings. Place your ring finger on the 3rd fret of the G string and your pinky finger on the 3rd fret of the C string. Strum all four strings and check that each one rings cleanly.
Root
Bb
Quality
Suspended 4th
Notes
Bb · Eb · F
How the Bbsus4 chord works
Bb
Root(1)
The home note. It gives the chord its name.
Eb
Perfect fourth(4)
A suspended fourth that replaces the third.
F
Perfect fifth(5)
Adds strength and stability.