This is not a matter of Sacred Music, but something which some Traditional communities grapple with, or conveniently ignore: how to incense the Blessed Sacrament during a Eucharistic Procession.
There are three easy steps:
- Walk forward, ahead of the Blessed Sacrament.
- Look backward, towards the Blessed Sacrament.
- Swing the censer sideways.
These are not our own fabrication. Please, our Lord deserves more than the mere designs of mere mortals. These, rather, come from a decree issued by the Sacred Congregation of Rites on 15 September 1742. Read them at your leisure from the link indicated towards the end of this post.
First, here is an illustration (click to enlarge) from the Missal:
And then, here is an old photograph (click to enlarge) of an actual Eucharistic Procession:
The number of thurifers is a no-brainer: at least one; at most two. Again, this figure is quoted from a decree of the Sacred Congregation of Rites, this time issued on 11 May 1878.
Now, read the decrees here.
Ut in omnibus laudetur Dominus.
Cappella Gregoriana Sanctæ Cæciliæ olim Xicatunensis 