Hi Randy, I'm glad you enjoyed the article.
First, a disclaimer: I'm currently in the process of getting the blue card not connected to any employer, but I haven't completed it yet, so my understanding could be incorrect.
If you have more than two years of work in Germany, you are allowed either option. But the blue card not tied to an employer is simply better; it is the same as the usual blue card, but with more freedom for you.
For example, with the normal blue card, if you switch jobs, it must be approved before you actually start working. Otherwise, you are probably working illegally. And during these Covid-times, this approval can take a month or more. It isn't so annoying if you're coming from a job with a long notice period anyways, but it is more annoying when already unemployed. If you had the blue card not attached to any employer, then you could start working immediately.
So to answer your first question, "which steps should I do?" ideally, since a blue card not attached to an employer is better, you would not follow the steps listed in the article, but some different steps. And they could be done in preparation; there is no requirement to be starting a new job—you could apply while at your current job.
Now for your second question, "what are the steps?" I'm hesitant to give specific details because I haven't completed it myself yet. But as an easy way to start, I recommend writing the Hamburg Welcome Center an email, something like, "Hello, I have worked in Germany for more than two years, and want to apply for a blue card not attached to an employer. Is this possible? Thanks." From there, I imagine they will guide you through the process.
When I have completed this process personally, I will write another article about it. But in the meantime, if you have any other questions, feel free to ask here. :^)
But as always: I am not a lawyer, and this is not legal advice.
Best of luck!