You can do it on an acoustic guitar even, it's all about digging your thumb in and nailing your technique. That said, high gain, a compressed tonality, high-output compressed (active) pickups, fresh strings and low string height help TREMENDOUSLY!
The way Dime is explaining here looks like you play any note and do a pull off from whatever fret to open, as you do that push the whammy bar down. Then on your way back up with the whammy bar, simply touch a natural harmonic.
If your just starting it may be easier to just hit a natural harmonic then whammy away.
For myself, its easier and sounds better with my od pedal. After seeing this video I now want a delay pedal.