As I have a fairly good grasp of the text in Latin of the Roman Canon, I can follow the priest's gestures and tell what he's praying and consider the words he's using as he prays. This is what I do, if not singing, while the priest prays the Te igitur, Memento Domine, and Communicantes...
When "all orthodox and keepers of the catholic and apostolic faith" - that is, all bishops - are prayed for after the Pope, I tend to call to mind my old parish priest, now Bp Jarrett of Lismore, and also various other prelates of my acquaintance! Of course, at the memento vivorum and memento defunctorum, I tend to call to mind those living and dead that I wish to pray for, as I expect everyone does. (Dominican priests keep their hands joined for the whole of both Memento's, not just while pausing to remember whomsoever they wish, which I think is a good practice.)
At the Hanc igitur, my practice if in the pews is to bow (as the Dominican Rite bids the priest to do, following the earlier Roman practice) and say those words, praying the Lord to receive the sacrifice of our lives (cf. Rom. xii, 1) united to the Sacrifice of His Christ, praying for deliverance from damnation, to be numbered among the flock of the Good Shepherd.
In the Novus Ordo at the Epiclesis I usually would pray Jube, Domine, benedicere - Veni, Sancte Spiritus - Veni, Domine Jesu; but strangely enough I don't do this at the Traditional Mass, why I don't know. I do at the Latin Mass think on the words of Consecration; at the Novus Ordo, I would sometimes add a silent Amen as the priest says them. Or, as the Mozarabic Rite adds, I may pray in my heart, Sic credimus, Domine Jesu - "So I believe, Lord Jesus [that these words spoken have truly effected all they signify]."
Of course, in my place as I kneel, I bow low at the Consecration and adore at the Elevation, praying as I posted earlier... and by my posture doing the same: as the priest genuflects, I bow myself down, and then as I look up at my God I make the saving sign of the Cross and strike my breast. Who could do less? (It must be added that when I serve Mass, I am of course not my own, and must fulfil my duty at this supreme moment by ringing the bell and lifting the priest's chasuble for him, while making my silent adoration, and of course bowing down when he consecrates and when genuflects, as is the custom.)
I honestly would prefer it if the priest could read the Canon and observe the Dominican and other mediæval rubrics, which I think help bring out the sentiment of the prayers:
- to bow low at the Hanc igitur (as mentioned above), uniting one's frail mortal service of the Lord with the all-availing Sacrifice about to be rendered present, begging to win heaven and escape hell;
- to extend one's arms in the form of the Cross at the Unde et memores, signalling with the body that the anamnesis of the Passion and death of Our Lord, the recalling of His mighty acts, is being carried out, and that remembering we offer the Divine Victim (the Theothyte) as our great oblation and sacrifice for the living and the dead;
- to spread out one's hands over the consecrated elements, not at the Hanc igitur but at the Supra quæ propitio (as the very words suggest, "Upon the Which do Thou with a propitious and serene countenance deign to look", and as was commonly done in Germany throughout the middle ages);
- to bow low, but with arms crossed (manibus cancellatis) at the Supplices te rogamus - again, as was the older Roman practice conserved by the Friars Preachers;
- to bow to the Sacred Mysteries at the Little Elevation, which is done by the Dominicans also, but, very curiously, done by them in stead of making the actual elevation!
While it would be singular and odd to actually stretch out my arms crosswise after the Elevation, I certainly call this gesture to mind as I recall the great work of our redemption thus accomplished by Our Lord stretching out His arms to save us upon the bitter Rood. Likewise I recall the erstwhile gesture made in divers places at the Supra quæ, and I do in fact bow myself arms crossed (if not serving of course -then I must observe a kneeling posture without oddities) at the Supplices te rogamus as I pray God may, receiving our Sacrifice at His heavenly altar, vouchsafe us (who dare come to communicate) every celestial benediction and grace. Whether serving or not, I cross myself when the priest does at these words.
Having prayed the Memento etiam, I strike my breast (except if I'm serving - the server has long been forbidden to do so, by decision of the Sacred Congregation of Rites) when the priest lifts up his voice at the Nobis quoque peccatoribus, and run through the list of saints in my mind, praying that we may indeed have some part and fellowship with them, the Lord not counting our just deserts but granting us forgiveness.
I especially pray the incomparable doxology of the Canon, and bow (Dominican, again! and I've noticed Aaron when serving or being M.C. does the same) at omnis honor et gloria:
et cum ip+so,
et in ip+so,
est tibi Deo Patri + omnipotenti,
in unitate Spiritus + Sancti,
omnis honor et gloria,
per omnia sæcula sæculorum.