Whoosh is awesome! I also use the little Zeiss Lens Cleaning Wipes from Walmart. Zeiss is the manufacture of really great optics and I trust these. They do a really great job. And of course, t-shirts are always good too!
I always apply a glass screen protector and a case within a few minutes of opening all my iPhone and the X was no different. To clean the screen I just grab a clean microfiber cloth and I almost never take the phone out the case for the entire year until it’s time to upgrade.