Once you have restrung your guitar you should tune your strings up to concert pitch. At this point in time the strings still have a certain amount of settling in to do and any vigorous playing will send them clean out of whack tuning wise.
The secret to getting your new strings to stay in tune is to stretch them. So for each string follow the following procedure:
1. tune your string to the required pitch, leave your tuner plugged in.
2. using your thumb and forefinger somewhere between your neck and bridge gently pull the string away from the guitar backwards and forwards at a rightangle to the scratchplate.
3. play the string – it should be flat – so retune it bringing it back up to pitch.
4. repeat steps 2 and then three until the string stays in pitch.
5. repeat for all new strings.
Now, your strings will be ready to rock and roll so plug into your amp and give it some.
Cheers,

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