Watch the Building Augmented Chord Triads online guitar lesson by Rob Garland from Chord Navigator: CAGED Triads
An augmented chord (+) contains a root, 3rd, and #5th (sharpened or augmented 5th). Like the diminished chord, it's often used to create movement to another chord, for example: C - C+ - F - Fm
It's often used as a turnaround chord (ideal in blues) creating the need for a strong resolution, such as G+ - C. I'll use a C chord (C-A-G-E-D "E" shape) as an example played from the C root on the D-G-B-E strings. Raise the 5th (the note G to G# on the B string) and you have a C augmented triad.