First riff ever tabbed by me :D
there may be some small variations in there somewhere, but this is a general outline.
The first bar goes something like this i think:....
E|---------------------------|
B|---------------------------|
G|---------------------------|
D|----------------3----------|
A|-3h5--3h5-0h5------5--5----|
e|---------------------------|
[ Tab from: http://www.guitaretab.com/l/los-lobos/55884.html ]
You should be able to get the drift of it
E|---------------------------|---------------------------|
B|---------------------------|---------------------------|
G|---------------------------|---------------------------|
D|------------3--------------|--------------3------5-----|
A|--3h5--3h5-----5----5------|--3h5--3h5------5----------|
e|---------------------------|---------------------------|
