Hocketing is a technique where the same melodic line is split between multiple instruments (or voices), such that alternately one instrument sounds while the others rest. This technique dates back to the 13th and 14th century when it was primarily used in vocal music. By employing hocketing we can create some truly interesting trance arpeggios.
A great way to compose a lead melody (or an element that accompanies your main melody) is to take a chord progression and turn it into an arpeggio - a broken chord where the notes are played in sequence rather than at the same time. They really are a fundamental element in trance music that help create harmony and rhythmic interest.