What is the best way to practice?

[BlackHGT]

About me:
I would say I'm a mid-range sim racer.
I've been playing racing games for years and have had a steering wheel setup for a few years now. I play GT(7), Forza (Motorsport),F1 (24), WRC, Assetto Corsa, ACC or even Grid and PJ Cars.
In GT7 I got all the licenses, missions and track experiences to Gold.

I've studied a lot about car technology (suspension, gears, differentials, etc.) and racing techniques.
(trail braking, racing line, weight balance)

So I know a lot about the theory. And this has also made me better over the last few years.

Now I've had the feeling for a long time that I'm not getting any further.
I think this is mainly because I know the theory well, but the implementation is not yet so good 😅. How do you train these things?
How do you recognize your mistakes, successes and progress?

I look forward to learning from your experiences.

Translated with DeepL.com (free version)

 

[Lomic]

In CE I use the demo ghost, in time trials I use a ghost close to the gold time, and change for a faster if needed.

In some extreme cases, I download a video from the replay I want to emulate, a video of my best lap, and I play them in sync using Kinovea, and I slow down or pause video to compare both, to check where and when the guy in the replay I study is braking, releasing brakes, trail-braking, throttlind, iddling...