What are the accepted, recommended or unaccepted ways, currently, to receive the host? Is it o.k. to dip the host in the cup?
In speaking of receiving or communicating the consecrated bread or host the Instruction sometimes speaks simply of doing so in "the usual manner." The Instruction usually speaks of receiving and not taking. When giving the Body of the Lord to a communicant, the minister raises the host over the vessel and says, ‘The body of Christ.’ After the communicant has responded, ‘Amen,’ the host is placed carefully on the tongue or on the outstretched palm of the left hand." In my experience that is how Communion in the hand is and has been taught.
I think it safe to say that almost all, if not all, Roman Catholic liturgists discourage Communion by intinction. The sign value in intinction is not as full as drinking from the cup. I should think the reasons for an alcoholic priest communicating by intinction are obvious. In many cases the minimum of the consecrated wine thus consumed will not trigger the urge to drink. This is more important than the fuller sign value of drinking from the cup.