Then as stated, 
Not while lying down, nor while standing up.
Not with laughter (merriment), nor while strolling. Neither while eating and (meditational) seat shouldn’t be disturbed.
External continuum: not be mixed with voice.
Internal continuum: not be completely silent.
Secret continuum: be of single pointedness. Emit-gather be continued.
Not walk over hand-beads endowed with the holder of the string.

As mentioned, with great kindness by the Excellent Refuge, the late His Eminence Luding Khenchen Vajradhara Jamyang Tenpei Nyima founded the Ngor Evam Retreat Centre.Ever since, at the retreat centre, many retreatants including the venerable abbots and zhabdrung of Ngor along with other abbots and sangha members conducted their meditational retreats of uncommon deities of their own tradition such as Shree Hevajra as the primary deity. Retreats of other deities of the four classes of tantras has been taking place uninterruptedly to actualise the excellent and common attainments by the retreatants mentioned above. Retreats are ongoing these days.