OK. In the monastic Office, Vigils (which became the Office of Readings in the Liturgy of the Hours) had two nocturnes on ordinary days, three on Sundays. It was set up like this:
Invitatory
Hymn
Psalms with Antiphons (6 in the traditional monastic)
Verse
Scripture reading (OT or NT but not Gospel) divided into three sections (4 on Sundays) with a responsory between each.
Psalms with Antiphons (again 6)
Patristic or Hagiographic reading (on saint’s days) also into three or 4 sections
Responsory
Kyrie, collect and conclusion
On Sundays the 3d Nocturne would include 3 OT canticles plus the gospel plus a homily, or a reading from a Church father, and the Te Deum.
The modern LOTH only has one set of psalms and no psalmody between the readings. Some religious communities objected, saying this was too “light” for contemplative orders. Some Benedictines compelled to use the LOTH for valid reasons felt the same way. So in response the Congregation for Divine Worship and the Discipline of the Sacraments published in its periodical “Notitiae” instructions on how to do the Office of Readings in two nocturnes (most contemplatives would use it as a night office):
http://www.cultodivino.va/content/cultodivino/it/rivista-notitiae/indici-annate/1974/89.html
Unfortunately the instructions are in French only but the gist of it is this:
Invitatory or opening verse
Hymn
Psalmody with antiphons (3 psalms or sections of longer psalms)
Verse
Scripture reading
Responsory
Psalmody with antiphons as above
Verse
Patristic or hagiographic reading
Responsory
Collect
Conclusion.
And on Sundays, feasts and solemnities, a 3d nocturne using the “Vigils” canticles in the LOTH and a Gospel reading and Te Deum
It looks much more like the layout of the monastic Office. Moreover it puts the Office of Readings on a 2-week rotation rather than 4 week. You use the psalms of weeks 1 and 3 in those weeks, and weeks 2 and 4 in those weeks. There’s some trickery concerning verses so that they aren’t repeated outside Ordinary Time when there’s a greater selection.
There’s also a way to do the minor hours as well, but Benedictines don’t use it. We prefer the gradual psalms in the complementary psalter as they have traditionally been used at the minor hours.
Hope it helps!