I don’t have an easy time explaining “how” I generate a hypothesis while knowing so little - it feels like I just always have a “guess” at the answer to some topic, whether or not I even want to (though it often takes me a lot of effort to articulate the guess in words). The main thing I have to say about the “how” is that it just doesn’t matter: at this stage the hypothesis is more about setting the stage for more questions about investigation than about really trying to be right, so it seems sufficient to “just start rambling onto the page, and make any corrections/edits that my current state of knowledge already forces.”
I'm the opposite-- I have a strong hypothesis based off of what I call a "sensical, logical" line of thinking. Then I have to work at finding the wording for the questions to disprove or prove my hypothesis. That is my favorite part, though, and I always start to get distracted by this fascination I have for language. Words are so weighted and so careful, though, it's wonderful.... sigh I digress.