As you do that, always aim for precision in notes, rhythm, articulation, fingering, pedaling, ornaments, and hand and feet position. Remember to keep your fingers and feet in contact with the keys and pedals at all times.
In other words, do not lift them off the keyboards and pedalboard. This will help you to achieve precision, clarity, and control your releases of inner voices to a much higher degree.
So as you play Fragment 1, if you notice that you still make many mistakes, then I recommend going back to practice in 3 or 2 voice combinations or even in solo voices when necessary. This will ensure that this fragment will be learned in the most efficient manner.
After you have repeated previously learned material (measures 1 and 2) at least 3 times correctly in a row, now it is a time for you to take up the next fragment (measures 3-5).
Similarly to what you did yesterday, write in fingering and pedaling for those measures first. Don’t worry if are not sure about something at first. It is best not to spend hours and hours trying to figure out the best fingering. Just write what seems obvious to you and then start practicing. As you practice, many things will become clearer and usually you can make revisions and additions for fingering and pedaling.
Follow the same procedure when learning this fragment as you did yesterday:
Step 1: Practice solo voices separately (S, A, T, B).
Step 2: Practice 6 combinations of two voices (SA, ST, SB, AT, AB, TB).
Step 3: Practice 4 combinations of three voices (SAT, SAB, STB, ATB).
Step 4: Practice all four parts together (SATB).
The ornaments in the right hand part are mostly mordents (performed G, F sharp G) and a trill in measure 5. This trill should be played starting from the upper note (B) on the beat. In measure 3, you can also see a mordent in the left hand part. Again, here too start it from the upper note (D).
In measure 5, the left hand part has 2 lower note mordents which are more difficult to perform because of the added one extra voice. As always, be extra sure about the articulation (articulate legato) here.
The pedaling in measure 3 is a classic example of the descending scale which I recommend playing using alternate toe technique: right-left-right-left and so on. This will help you to achieve the natural feeling of alternation of strong and weak beats which are so crucial for the performance of Baroque music.
By the way, do you want to learn my special powerful techniques which help me to master any piece of organ music up to 10 times faster? If so, download my free video Organ Practice Guide.
Or if you want to learn to improvise in the style of Bach? If so, I suggest you check out my free 9 day mini course in Keyboard Prelude Improvisation.