Deleting things always work for me to clear the fog in my head. Your eyes are tricking you with complexity, so when you delete the inner part, things simplify a lot. For example:

If the interior part was full of faces and making a whole mess, my mind would be saturated. So I just delete all the inner faces and leave all the main simple shapes. It is then that my brain has a break and can clearly see how I can fill stuff the proper way.