Some notes of mine about the order for Mattins and Evensong found in the Customary:
The use of a Sentence of Scripture and Penitential Rite at the start of the Hour is allowed before Evensong only; the Penitential Rite consists of an Exhortation, a Confession and an Absolution (non-sacramental, of course): the Exhortation derives from Evensong, not Mattins, in the 1979 US BCP (this same passage was reused in the Book of Divine Worship); the particular form of the Confession also follows the US BCP and BDW in omitting the 1662 phrases "And there is no health in us", "O God", and "miserable offenders", as well as making slight changes in the use of personal pronouns from the more archaic "them which" and "them that", and also reading "Jesus" not "Jesu". Finally, the Absolution follows the BDW in adding "May" to make the subjunctive sense clear, and changing from the 1979 US BCP by reading "us" and "our", not "you" and "your":
Dearly beloved, we have come together in the presence of Almighty God our heavenly Father, to render thanks for the great benefits that we have received at his hands, to set forth his most worthy praise, to hear his holy Word, and to ask, for ourselves and on behalf of others, those things that are necessary for our life and our salvation. And so that we may prepare ourselves in heart and mind to worship him, let us kneel in silence, and with penitent and obedient hearts confess our sins, that we may obtain forgiveness by his infinite goodness and mercy.
Let us humbly confess our sins unto Almighty God.
Almighty and most merciful Father,we have erred and strayed from thy ways like lost sheep,we have followed too much the devices and desires of our own hearts,we have offended against thy holy laws,we have left undone those things which we ought to have done,and we have done those things which we ought not to have done.But thou, O Lord, have mercy upon us,spare thou those who confess their faults,restore thou those who are penitent,according to thy promises declared unto mankind in Christ Jesus our Lord;and grant, O most merciful Father, for his sake,that we may hereafter live a godly, righteous, and sober life,to the glory of thy holy Name. Amen.
May the Almighty and merciful Lord grant us absolution and remission of all our sins, true repentance, amendment of life, and the grace and consolation of his Holy Spirit. Amen.
At Evening Prayer, the first versicle “O Lord, open…” is omitted (just as in the 1979 US BCP), unless traditional musical settings are used; and the same applies to the use of the 1662 versicle “Praise ye the Lord” at both Morning and Evening Prayer – following the US BCP and BDW, "Alleluia" is proposed for use instead (in this imitating the Roman Rite).
The Morning Prayer Invitatories are all but one (the first) based on those in the 1979 US BCP, as also used in the BDW, but updating the language ever so slightly, as by using "draws" not "draweth", etc. The Invitatory Psalms suggested are either the traditional Ps 95 (not the US cento version), or one of Pss 24, 67, 100 (the last also in the BDW), or of course the Easter Anthems at their proper season.
As a parallel to the Invitatory, at Evensong there is an option to insert a Lucernarium: Ps 141:1-4b, 8 or Ps 134 or two hymn versions of the Phos hilaron may sung while candles are lit, and incense burned. This seems a trifle contrived, I must say.
As is traditional in Anglican practice, an Office hymn may be sung either after the Invitatory Psalm (at Mattins) or before the "Mag." (at Evensong).
The Psalmody follows in the usual manner; and, next, the two Lessons, with a Canticle after each.
Oddly, no direction is given as how to announce the title of the Lessons. Unlike in the 1662, allied BCP's, and the BDW, there is no provision to say at the close of each, "Here endeth the (First/Second) Lesson" but instead only "The Word of the Lord" with the usual Roman response may be used.
At Mattins, the appointed Canticles are: after the first Lesson, Benedicite or Benedictus es (ferial), or Te Deum (festal); and after the second, the Benedictus (daily) – however, the Customary gives three other canticles as optional alternatives to use after the first Lesson on Ash Wednesday (Deducant oculi, Jer 14:17-21), Good Friday (Domine audivi, Hab 3:2-4, 13a, 15-19) and Holy Saturday (Ego dixi, Is 38:10-14, 17-20, which may also be used on All Souls and in the Office for the Dead).
Similarly, at Evensong, the daily Canticles are the age-old "Mag. and Nunc" (or, if the latter is to be used at Compline, one of the modern Roman Vespers New Testament Canticles is to be substituted therefor).
After the Apostles' Creed, "The Lord be with you" (to be omitted if the person presiding is not a clergyman), "Let us pray", the threefold Kyrie (in English) and Lord's Prayer all follow. After the "Our Father" come the Suffrages, in three forms – the first set (A1) is the traditional English from the 1662 BCP; the second (A2) derives from the 1979 US BCP (via the BDW); the third (B), is also US in origin, at Mattins being the Te Deum’s third part, but at Evensong is Byzantine in origin.
The Collect of the Day is followed by the traditional Second and Third Collects; after these, the end of the service may include hymns or anthems, a sermon, Benediction of the Blessed Sacrament (at Evensong), and/or "Further Prayers" – among which are given: the General Thanksgiving (in traditional 1662 form), a Prayer for the Pope (an understandable insertion, with a text derived from the old Missale Romanum), a Prayer for the Clergy and People (1662 form, but with “Curates” changed to “Clergy”), a Prayer for the Queen and Royal Family (moved from before the prayer for the clergy to avoid any hint of Erastianism; again, not in the 1662 form, but with a text taken from the old Roman Missal's oratio pro Rege); and the famous Prayer of St Chrysostom (1662, derived from the Byzantine Divine Liturgy).
The whole service ends either with "The grace..." (1662) or with a more Roman conclusion: "The Lord be with you… Let us bless the Lord…" and either "The Lord bless us…" at Morning Prayer (derived from modern Roman Lauds and Vespers) or "May the souls of the faithful…" at Evening Prayer (from the traditional Roman Office).