Locking tuners
If you are having tune instability issues with your guitar, you may want to check out your tuners, especially if your guitar is in the < $200-300 MSRP range (if you are above that mark it is reasonable to believe that your tuners will be of slightly better quality). You can easily change your tuners to locking tuners, which have a locking wheel underneath. When you turn the wheel, the peg bites into the string and locks it into position. Because the string is locked, there's no need to wrap the string around the peg. Because there is no wrap, it is a lot harder to misjudge how much you are tightening the string, which means less chances of accidentally breaking the string. And because it is locked in place, there's no slip, so you will have better tune stability, you will still have to account for string stretching, humidity, etc. but at least your string length will be constant. A good quality set of these locking tuners will run around $50-60. You can go under $20 if y...