I’m glad you like my videos. However, they are not meant as tutorials but rather as a demonstration of how I use darktable. The idea behind it is to show people how to achieve certain results and to prove that darktable can achieve the same high quality results as proprietary software.
I find a general step-by-step tutorial very difficult - and this applies to all photo processing software - because there are different tasks and user cases that differ so much from each other.
But, if you have a concrete example of what you would like to achieve, you can provide us with the corresponding image and I will be happy to give you a step-by-step description of how I would process it with darktable.