Right Knee, Left Knee: Stuff They Don't Tell You in RCIA
Thanks to Ma Beck for these:
1) That motion with your right hand before the reading of theGospel is making three small crosses, with your thumb, on your forehead, lips, and heart. I was taught that it meant, "I will remember it with my head, proclaim it with my lips, and carry it in my heart."
2) If the Blessed Sacrament is exposed (at Communion, after Mass if someone from the choir is receiving Communion, during Adoration) you kneel on both knees. If you are genuflecting to the Tabernacle, it's on your right knee. If you're genuflecting to a Bishop, Cardinal, or Pope, it's on the left knee. (Update: This only applies to Bishops or Cardinals with jurisdiction over you - for instance, I would genuflect to Cdl. George, but not to Cdl. Mahony. For multiple reasons.)
3) Old habits die hard, and this is perhaps a leftover from Catholic school, but except in familiar conversation over dinner (and only then occasionally), it's better to say, "Yes, Father" or "No, Father" than "Yeah", "Yep"*, or anything like that. And while we're on the subject, standing up briefly when a priest (or a woman) enters the room is always appreciated.
4) In the Tridentine Mass, the priest will say something to you before you receive Holy Communion. No response is necessary. (You might notice it ends with him saying "Amen.")In the new Mass, no matter if it's in Latin (11AM) or English (9AM), you respond "Amen."
5) Seriously, stick that tongue on out there. Waaaay out there. Don't be afraid. But for his sake, brush your teeth before Mass and go to Mass before you drink coffee.
6) In the new Mass, you kneel AFTER the Angus Dei and AFTER the Sanctus, unlike the Tridentine Mass. This applies to the new Mass no matter if it's in English, French, Latin, or Vulcan.
7) Often, during the announcements, the priest or deacon will say "Today's Mass is offered for the repose of the soul of Stanislaus Sczweszjszweski. Eternal rest grant unto him, O Lord."The response of the people is "And let perpetual light shine upon him." Then we make the Sign of the Cross while the priest says "May his soul and all the souls of the faithful departed through the mercy of God rest in peace" and we say "Amen."
8) But most of all, if there's something you don't understand or can't quite figure out, just ask. Someone will be happy to answer your question, and you aren't expected to know everything.