One example of string skipping involves string bending on the 7th fret of the G string, then jumping to the 8th fret of the E string (skipping the B string). Another way to achieve the desired aesthetic is when playing a thrash riff while chugging open E's, to pick strings E, B, G, or D to play extra notes in the riff.
How can I improve my string skipping?
String-Skipping Tips:
The only way to really improve your string skipping is to watch your picking hand while you do it. This is the secret to improving picking-hand accuracy. If possible, memorize some of these exercises or etudes so that you can do this work while staring at your picking hand the whole time.
Why is string skipping hard?
String skipping can be difficult to master during single lines, where errors are more obvious than they are for chords. Try playing this pentatonic scale using a string-skipping pattern, and then adapt it to the other four pentatonic scale positions.