Don't! I also have the same problem if I wear headphones for too long, usually 2-3 hours, so about the same as you (got the Bose QC35), so I usually only use those headphones when I want to make sure I remove bright noises from the environment, like airplanes.
Otherwise, at home (which is 100% of my time because of the lockdown) I use speakers (same for showers, using speakers). Then office environment I usually have my in-ear headphones that have superior bass compared to my headphones and I can wear them for the full day without feeling anything on the top of my head or my ears.
I wish! But I have the pleasure of working in an "open office"... I have to wear headphones (or 3M construction earmuffs/PPE when I don't want music) just so I can hear myself think in the middle of all the chatter.
It makes my ears too itchy inside if I wear cupped headphones for more than 3-4 hours straight. My theory is that it build up humidity from my body but it's not ventilated because the headphones' cups are tight.
Anyone else with that problem? How do you avoid itchy ears after wearing headphones for longer times?