The same sweep picking technique applies to all numbers of string groupings. Continue to develop arpeggios using triads, seventh chords, ninth chords and more. Not every sweep pattern has to be a triad. In this lesson, we will sweep power chords over four strings. Because four strings are used, it is easy to place these patterns over a beat in 16th notes (four notes per beat). Also, it sounds absolutely crazy!

You should take scale and chord knowledge and develop your own shapes to get unique sounds out of the guitar. The sweep picking technique is the same regardless of the shape chosen, so the shapes you use can be infinite and exciting. There are more online guitar lessons. There is also a great video that teaches four string sweep picking below.
Another excellent sweep picking lesson below: