My teacher assigned me this piece for the vacation. How do I start practicing this etude? Any tips on starting the piece? Any advice is welcome. Thank you.
You can start by making a harmonic analysis, I think it´s pretty clear for most of the part, (triads and sometimes 4-3 notes) also, keep an eye on the Dies Irae motif, analyze how it moves along the harmony and the different voices. Talking about other voices, you can also practice them separately and then trying different combinations, as in a fugue.

sorry, I was thinking of the op.39 lol, but still, my suggestions would be pretty much the same, harmonic analysis and practicing every voice separately (the rhythmic pattern and the main melody)