An example:
e-5----------5-
b--5--------5--
g---5------5---
D----5----5----
The first part are all upstrokes , and the second part is all dowsntrokes.
All are natural harmonics of course , you can do them from any harmonic spot of course , even unusal frets like 3rd , 2.5 or whatever you want.
If you listen to Joe Satriani , try playing "Up in the Sky" ... The intro is a very good exercise on that harmonic raking technique.
