01 Set your Intonation
Intonation is the term used to describe how in tune your guitar is across its scale length. It needs to be set right, or your tuning won’t be consistent at different positions on the neck. To set your intonation yourself, string up with a fresh but stable set of strings. Play a harmonic at the 12th fret, then fret the note at the 12th fret. If your tuner reads the fretted note as sharp you need to move that string’s saddle away from the neck (flattening the tuning), and if it reads flat move the saddle toward the neck (sharpening the tuning). On a Strat this is adjusted with a screwdriver at the back of the bridge, but the same principle applies to tune-o-matic type bridges too.
Use a screwdriver to change the pitch of your string until the fretted note matches the harmonic. Repeat this for each string and your intonation will be set
With a freshly-settled and tuned-up set of strings, play a harmonic at the 12th fret followed by a fretted note
Your guitar’s bridge has screws to move the position of the string saddle and set the intonation of your guitar