The following directions are subject to variation according to local custom.
At High or Low Mass, the triple bell at the celebrant's Domine, non sum dignus is the signal for the faithful to approach the altar rails for Holy Communion. Anyone standing in the aisles should kneel for the Ecce Agnus Dei.
As the priest enters, the congregation should kneel.
From beginning to Gospel kneel
At the Gospel stand
At the Credo stand During the Offertory sit
From the Sanctus to the Last Gospel kneel
At the Last Gospel stand
Post-Missal prayers and exit of priest kneel
During the processional entry stand
During the Asperges stand
From beginning to Gloria kneel
At the intoning of the Gloria stand
If the congregation sings, remain standing. If the choir only, sit when the clergy do. Rise with the celebrant for:
Dominus Vobiscum and Collects stand
At the singing of the Epistle sit
At the singing of the Gospel stand
At the notices and for the Sermon sit
At the Credo stand
As at the Gloria. Rise with the celebrant for: Dominus Vobiscum, Oremus stand
During the Offertory sit
Rise when the congregation is incensed
Preface dialogue to Sanctus stand
Sanctus, Canon, Communion kneel
Dominus Vobiscum and Post Communion stand
At the Blessing kneel
Last Gospel to exit of clergy stand