I have also become much more conscious of what I don't quite want to call "pet peeves" because, while they are things that bug me, they aren't unimportant or silly as, I assure you some of my other "pet peeves" are.
The one that is on my mind these weeks has to do with receiving the Eucharist. Now I've not yet had anything so bad as the communicant who, according to a Jesuit friend, came to communion talking on his cell phone, but I am tempted to give an instruction on receiving the Eucharist. Now, I'm sure that my readers are not guilty of such things, but maybe you could tell your friends. This is what I would say:
First, and this might actually make the difference, consider that the Eucharist is something that you probably actually want to receive. How might you approach the Eucharist as if it were something you really wanted?
Second, imagine if someone were about to give you something that you not only really wanted, but also really needed, where and how would you hold your hands to receive it? Would you hold your hands so low that the person would have to risk back injury to give it to you, or just casually stick out one hand as if unconcerned where what you are receiving might end up? Or wouldn't you hold both hands up high, near those of the person giving it you, so as not to lose something precious?
Note: when you don't hold your hands up high, you cause confusion, because the priest or eucharistic minister, not seeing your hands, will presume you're receiving by mouth, the result being further confusion when you don't open your mouth.
I was a child when communion in the hand was first introduced, and I think the way we were trained to receive still works well: Hold your hands high, left hand placed over right, so that the Eucharistic minister can easily place the bread into your hand. It's that simple.
Third, patience. "Amen" is a response. You're saying "yes" to something! Don't preempt me by saying "Amen" before I say anything. Wait until the priest or eucharistic minister says, "Body of Christ," and then say "Amen." And you silent types, overcome your shyness and at least say "Amen," don't just stand there and say nothing. Also, it's not a time to chat, so stick to "Amen" and avoid such things as "how are you?" and "have a nice day!"
Fourth. You may never have considered this, but priests and eucharistic ministers of my age (40) and younger tended to be brought up receiving communion in the hand, or at least knowing that was the way the majority of people received. So, as a result, when you come for communion by mouth, this can be a source of anxiety. There is more danger of something going wrong, like dropping the bread, or touching someone's mouth. This is not to discourage anyone from receiving this way, but just FYI. You can help alleviate that anxiety, and protect against such accidents by opening your mouth fairly wide, and sticking that tongue out (not all the way).
Fifth. It was because of things like this that the Church recently asked people to bow their heads before receiving communion. This is good for helping you to remember that the Eucharist is something you actually want to receive!
Finally, a note on intinction. Some people have become accustomed to dipping the bread in the wine, and then receiving the bread that way. This is actually the common practice in some eastern rite Catholic churches. But most people do not intinct the way it is supposed to be done. The proper way is to hand the bread to the eucharistic minister and let them dip the bread in the wine. They can then give it to you on the tongue.
Again, I think the first thing is more or less the cure for all ills. Remember that the Eucharist is something that you want and need, and is worthy of reverence. The rest, then, would more or less take care of itself.
