Standard guitar tuning method

Standard Guitar Tuning Method
Step 1:
The E String (Thick one). Tune the bottom E, as accurately as you can. Chances are it’s in tune anyways, being the thickest string it’s the least likely to detune itself than any of the others. If you have another instrument such as a Piano (which stays in tune for years), you can tune it to the 1st E below middle C. If you have no device or instrument handy just try to get it as accurate as possible, what really counts when you are playing is that the guitar is in tune with itself and any other instruments you might be playing with.

Step 2:
The A StringPlace the first finger of your left hand just behind the fifth fret on the bottom E string. That’s an A note. Keep your finger on that fret. Now pick the fifth and six strings in turn, gently adjusting the fifth string tuning peg until the two notes are the same.

Step 3:
The D StringPlace the first finger of your left hand just behind the fifth fret on the A string. That’s a D note. Tune the 4th string (the D note) to that.

Step 4:
The G StringPlace the first finger of your left hand just behind the fifth fret on the D string. That’s a G note. Tune your G string to that note.

Step 5:
The B StringPlace the first finger of your left hand just behind the forth fret (note the B string is the only one that comes from a different position the forth fret, the rest are from the 5th fret).

Step 6:
Tuning the E StringPlace the first finger of your left hand just behind the fifth fret on the B string. That’s a E note.


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This is copy pasted from here. You can found many usefull things there.
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