Performance:

Instead of pushing the string between metal strips with left hand finger on the fretboard as with regular notes,
softly touch the string directly above the metal strip (the strip that located closer to pickups)

and stroke it with the right hand as usual, after the stroking immediately take off the finger of the left hand

out of the string. And you'll get bell like sound.

watch video example

The easiest place to play natural harmonics on the fretboard is over 4th, 5th, 7th,  12th, 16th 24th  frets.

Almost all natural harmonics gives higher note frequency than any other regular played note.

Natural harmonic over 24th fret sounds the same as natural harmonic over 5th fret.

In guitar tabs natural harmonic has following notation:

In simple notepad tablatures it usually marked as a note between square brackets  <>.

1|----------------

2|----------------

3|-----<12>-------

4|----------------

5|----------------

6|----------------

Also sometimes natural harmonic can be notated as symbol "+" or N.H. letters above the tab.

Little lick to practice natural harmonic playing.

video example