Watch the Triad Shapes online guitar lesson by Matthieu Brandt from Guitar Lab: Triads and Hendrixian Double Stops
In this lesson we'll give you a resume of the general principles of the triad system and how to use it on the middle three strings; strings two, three and four.
The goal you are aiming for is to create a smooth backup part, without attracting too much attention. No jumping around on the fret board allowed. When you use triads you often have more than one option when you move around from one chord to the other.