If the parish doesn’t conduct a procession or observe the solemn entrance, the people come to church, just like for any other Mass.
43. If the solemn entrance cannot take place the simple entrance is used. When the people are assembled, the bishop and the concelebrating priests, the deacons, and the ministers, each in appropriate vestments, preceded by the crossbearer, go from the sacristy through the main body of the church to the sanctuary.
44. If there are relics of the saints to be placed beneath the altar, these are brought in the entrance procession to the sanctuary from the vesting room or the chapel where since the vigil they have been exposed for the veneration of the people. For a just cause before the celebration begins, the relics may be placed between lighted torches in a suitable part of the sanctuary.
Section 45 designates that Psalm 122 or “another appropriate song” may be sung. Interesting that Psalm 24 is superceded here. Also interesting is the suggested antiphon for the 122nd:
God in his holy dwelling, God who has gathered us together in his house: he will strengthen and console his people.
Option 2 is “Let us go rejoicing …”
RDCA II, 46 gives the episcopal greeting from the sanctuary after the procession concludes, as in II,30, but without the introductory remarks. The presentation of representatives (cf. II, 33) is covered in section 47.