Speak to Hashem until your soul is about to depart
It is necessary to converse and speak between oneself and his Creator, and to truly arouse ones heart so much, to the extent that his soul will just about depart, Heaven forbid, and this is the main completeness (/perfection) of hisbodidus.
(Likutay Moharan II, Torah 99; Outpouring of the Soul 7)