How to bring out these subjects in the fugue?

[m1kes_]

I'm currently learning the fugue in A-Flat Major of the 1st WTC by JS Bach (BWV862). I already have it memorized and know the voices separetely quite well. But now I'm trying to bring out the subject. I am managing to do it throughout the fugue except for these spots, I don't know to practice this passages where I want to bring out a voice that is not played between both hands and isn't the melody or the bass. I don't know to practice it to manage to bring out the subject.

Do you have any tips? The spots are the following ones:

[brogers70]

This may not seem very specific, but what I've found helps is this. Play the passage and just listen for the subject. Once you can hear it, play through the passage until you can hear it more clearly. It sets up a sort of biofeedback, and your hands/fingers figure out how to bring it out on their own, without your having to think about striking some fingers more forcefully than others.

Another, more physical thing you can try is just to play all the notes that are not the subject staccato, playing quite slowly. Still, I find just listening for the voice I want to bring out helps more than anything else.

[dizzyfingers]

brogers70's suggestion of articulating the secondary line differently (staccato) is a good one.
Apply slow practice striking the fugue theme with greater force and the non-theme notes with much less.  At first you may not have the muscle control in your fingers/hand but eventually you will.  It's a skill all Bach musicians need to learn, it will come in handy in many pieces by other composers.

[lelle]

You can use held note exercises to practice independent finger control but I'd advice against using these exercises without a knowledgeable teacher who can help you do them safely. They can be quite dangerous to your playing if you do them without knowing what you are doing.

Another exercise you could do would be the following:
Play a five note cluster, i e a chord containing CDEFG
Play the chord repeatedly but slowly
Each repetition, bring out one note loudly while keeping the others fairly quiet

Example, with capital letter representing the loud note, small letters the quiet notes
Cdefg, cDefg, cdEfg, cdeFg, cdefG, cdeFg, cdEfg, cDefg
Keep repeating

Try to make the loud note as loud as possible, quiet notes as quiet as possible, without tensing up. You should aim to be quite relaxed doing this.