Watch the Scarborough Fair Pattern online guitar lesson by TrueFire from Play Acoustic Guitar 8: Advanced Techniques
Scarborough Fair Pattern - Technique #22 is a video guitar lesson presented by Muriel Anderson and is sourced from 50 Right-Hand Techniques You Must Know.
The pattern used in Paul Simon's accompaniment to "Scarborough Fair" is particularly beautiful because it has the bass notes on every 3rd note instead of every 2nd note or every 4th note.
This makes it sound like a 6/8 time pattern played over a 3/4 time song. Because the strings are in a different order than you may usually play them, it makes for a great right hand exercise as well.