Watch the Angle of the Thumbpick online guitar lesson by TrueFire from Play Acoustic Guitar 5: Fingerstyle Principles
Angle of the Thumbpick - Overview is a video guitar lesson presented by Tommy Emmanuel and is sourced from Fingerstyle Milestones.
I just want to show you and talk quickly about the angle of my thumb when I'm playing this boom chick bass. As you can see my thumb is literally parallel to the string. I'm not moving very much, the thumb is just moving enough to spell out those notes. If you start doing stuff like putting your thumb at an angle, it's going to sound worse, and look silly, which we definitely do not want. You see, when it's parallel I'm getting a lot of clarity out of those notes and minimal pick noise. So be concious of the angle that your thumb is at. Now, I've prepared some exercises for you.