HI John, Idealy to set up the String lengths ( Intonation ) you'll need an electronic tuner:
Starting with the thick E string you tune it to E, then fret the same string at the 12th fret and it should be a higher E, if it isn't you adjust the string length adjusting screw and try again - when both the open E and the 12 fret E are bringing the tuner needle to the middle - the string length is correct
Repeat the procedure with all the other strings.

String Height adjustment ( Action ) is simply raising the string height untill you lose all the fret buzz