Changing your guitar strings
Tuning your guitar after replacing the strings takes a little patience, as strings stretch and the guitar itself flexes – even a modern electric guitar is still made out of a natural product (wood, dummy!) and it takes a little while for it to stabilise. It’s best not to remove all your strings at once, but to change them one at a time; this keeps tension on the neck.
If you've just restrung your guitar, grab the middle of each string in turn (around the 12th fret) and gently pull it up and away from the guitar – this helps to pre-stretch the strings and helps them to settle down quicker.
When you tune your guitar and vary the tension on one string, your guitar flexes a little, changing the tension on the other strings. So it’s almost impossible to get the tuning right first time, even if you have an electronic tuner. Just tune each string approximately first and when you have got all strings roughly in tune then repeat, becoming fussier and more accurate about the exact tuning. Here’s a good online tuner… but if you haven’t got one, why not buy one now? They’re cheap enough… and pretty cool toys! (check out Guitar Accessories)
All new strings take a little while to settle down, with Nylon strings for classical guitars taking longer to stretch and settle into tune than steel ones.
Old guitar strings get flattened where they contact the fret wire and become dull sounding and difficult to keep in tune. That's when you really need to change them!