For Catholics: The Proper Sign of Veneration before Communion

I didn't know this: before receiving Communion Catholics in the United States are obliged to simply bow their heads. Via the USCCB:

Sign of Veneration
In a similar way, the General Instruction (no. 160§2) assigns to Conferences of Bishops the responsibility to determine "an appropriate gesture of reverence" to be made before receiving the Blessed Sacrament. Thus, in the dioceses of the United States of America, the communicant is directed by this particular law to "bow his or her head before the sacrament as a gesture of reverence and receive the Body of the Lord from the minister."

Uniformity in Posture
The General Instruction of the Roman Missal emphasizes that in matters of gesture and posture "greater attention needs to be paid to what is laid down by liturgical law and by the traditional practice of the Roman Rite, for the sake of the common spiritual good of the people of God rather than to personal inclination arbitrary choice" (Girm, no.42)/ Throughout their consideration of GIRM numbers 43 and 160, the Bishops repeatedly recalled the need for uniformity in all prescribed postures and gestures.

Such uniformity serves as a "sign of the unity of the members of the Christian community gathered for the sacred Liturgy" and it "both expresses and fosters the spiritual attitude of those assisting" (GIRM, no. 42). Likewise, a lack of uniformity can serve as a sign of disunity or even a sense of individualism. A particular example of this disunity has been cited by many of the Bishops in regard to a diversity of postures during the Eucharistic Prayer, "the center and summit of the entire celebration" (GIRM, no. 78). Thus, the variation from kneeling as the uniform posture during the Eucharistic Prayer is permitted only "on occasion" and when the circumstances found by GIRM (no. 43) are clearly present.

Personal forms of veneration are explicitly condemned. This makes sense; I should have looked this up years ago!