5 ways to preserve a guitar's tuning:
1. Keep the guitar standing up and not lying down. This avoids putting and pressure on the turn keys and thus maintains your tuning more or less.
2. Never put petroleum jelly on the strings after tuning (before playing every time, that is). The jelly makes the strings thicken up disproportionately and hence you lose the tune.
3. Never leave your guitar anywhere where it can be exposed to the sun or cold or moisture. Remember - its wood and metal (delicate) - treat it like you will do with your cell phone or watch.
4. Never hold the guitar by its head- you will surely turn the keys. Hold it by its neck.
5. Keep away from idiots unless you can redo the tuning yourself. It never ceases to amaze me, how many people lose their tuning to their friend's overenthusiastic zeal to learn from them.
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