Ha, you are right, I have too many guitars going
Number 1+2 are finished, number 3 and 4 get finished ;-)

But here comes the good news:
I *think* I found a routine that is now working for me. I did integrate a lot of your advice!

* First, I clean the surface with a soft cloth.
* Step two: Put on a fresh rubber glove and rub the surface with it. This works great for pulling off all sorts of tiny hairs and dust.
* Step three: I use lint free, lab grade cotton paper towels. Fold all the corners inside, and then fold it in the middle, so it has all soft edges and two usable sides (important, and a great tip from you guys).
* Step three: Dip it in the poly and apply in circular motions, while applying some light pressure. This step seems to pull out even more of the crud from the last layer, so here comes the next important step:
* Flip the folded cotton towel and now use the unused side to pull down the poly from one edge to the next (I do top to bottom) without lifting or stopping. This ensures the crud is trapped on the other side and I use the fresh side to even out the poly.

Of course, it is still impossible to have a completely dust free surface in my environment. I don't have a dedicated work space (currently using the kitchen table) cause we live in a pretty small flat with two hairy pugs. No cellar, no basement, no garden. So I'm trying to make the best of it.

Anyway, thank you very much for all your great advice and maybe my workflow above does help out somebody else who maybe found this thread on google