"Trekcho is to simply acknowledge that one's innate essence is empty. Togal is to recognize that the natural display is spontaneously present. They are not our creation; they are not produced by practice. There is no imagining of anything in either trekcho or togal.
"Without cutting through with treckcho, you can't directly cross with togal."
Tulku Urgyen Rinpoche
(Vajra Speech, pg 174)
my footnote: the term lhun grub, translated here as "spontaneously present" is a very important term in dzogchen. lhun encompasses the notions of being effortless, natural, spontaneous; while grub means accomplished, formed, come into being. Togal is typically translated as direct crossing or direct leap, and refers to spontaneously crossing the illusory gap between self and other, subject and object, the perceiver and the perceived. In short, one effortlessly and spontaneously shifts from one's habitual dualistic perspective directly to the nonduality that is innate rigpa.