With questions like this - the help and the tour are your starting points.
I don't have a question but actually some kind of advice for hopefully a number of superusers around there?
Er... depends. Can you frame it as a question? Is it a solution for a real problem with a real solution?
Should I first ask the question, wait a bit and than answer my own question?
[Self answering is fine][1]Self answering is fine - you can even tick a little check mark to self answer immediately if you want.
Make two accounts one for asking one for answering? (probably a bad idea).
In this case, not a good idea. Some folk do have alternate accounts and you [can find the official rules on that here][2]can find the official rules on that here
These aren't boards, these are Q&A sites, and we do work a bit differently. Does look like you roughly get that though. [1]: https://stackoverflow.blog/2011/07/01/its-ok-to-ask-and-answer-your-own-questions/ [2]: How should sockpuppets be handled on Stack Exchange?