I know it is stupid question, but honestly, I can't find any link that would point me there.
Maybe it doesn't exist in a way I expect it to find? Maybe there is no wiki per se, and one makes entry to wiki just by putting some special tag to the question?
Community-wiki status (this is not a tag) is generally added by moderators, so the best way to indicate that your post should be converted to CW is to flag your question for moderator attention. There are some cases where a post will turn to CW automagically (see examples in the previous link). Answers can be made CW by the user directly (by checking the box in the bottom right of the response panel in editing mode).
