The height of your strings greatly effects playing. If the strings are too high, it may be difficult to finger the notes with your left hand, and certain techniques like fingerstyle (tapping) maybe be overly difficult. Conversely, if the strings are too low, they may hit the fret board producing distasteful sounds. Thus a happy medium must be found for each string.
Personally, I have my thicker lower strings much higher so I can play with gusto, while my high strings are by the tip of the fret board for ease when finger tapping. Everyone will have their own personal taste when it comes to string height.
Take note of the distance from both the fret board and pick ups.
Check to see when the bass is played, does it feel difficult to play high notes on your low strings, or do any notes produce a metallic sound when played.
Locate upon the bridge the hex screw that corresponds with the string which is either too high or too low.
Note: In this guide we will be making the B string higher. So we will adjust the B strings hex screw.
Using the hex screw, turn clockwise to raise the string and counter clockwise to lower the string.
While trying to raise the string: Pluck the string after each quarter turn to determine whether the metallic sound has gone.
While trying to lower a string: Pluck the string after each quarter turn to see if a metallic vibration can be felt.
Adjust the string height to your preference.