Locking tuners are a recent development in guitar technology. Locking tuners take the guesswork out of stringing a guitar, and at the same time, insure a permanent bond of string to neck. Install locking tuners the same way you install normal tuners. Locking tuners will make your guitar more valuable.
Pick up the guitar. Tilt it backwards so that the back of the guitar is facing you. On the back of the headstock there are six knobs. Turn each one of the knobs counter-clockwise two or three turns until the knob is loose.
Lay the guitar in your lap facing up. Turn each one of the tuning keys on the headstock, rotating the holes in the post to face the guitar nut.
Remove the biggest string from the package and slide it through the corresponding tailpiece hole of the guitar, letting the nut on the bottom of the string bottom out. Slide the other end of the string through the corresponding hole on the tuner peg.
Pull the string tightly with your left hand. With your right hand, turn the knob clockwise on the back of the tuner to lock the string in place.
Remove all the strings from their packaging. Slide them through the tailpiece and corresponding tuner pegs, one at a time. Pull tightly with your left hand and tighten the nuts on the back of the tuners with your right hand.
Tune the guitar normally to pitch with an online tuner or by ear. Trim the ends of the strings off with wire cutters. Fine-tune the guitar to pitch.
Some locking tuners have different features. One type will cut the string off for you inside the tuner peg. The end of the string will fall off by itself. Another type of locking tuner has the locking mechanism on top of the tuning peg. It works the same way, except use a small straight screwdriver to lock the string after you thread it through the peg.
Guitar strings can puncture skin. Be careful of the sharp ends around your eyes.