Don't want to be disturbed? Then let the FA know what seat you are in and just tell them: "Hi, I'm Philoj sitting in (insert seat here), I just want to relax in peace and request not to be disturbed today. Thank you"

Even though the FA may look at you funny, but at least you informed them that you just want to be left alone.

Another good indication is once you are airborne, put the blanket/duvet around you, with the seatbelt visible on the outside, put a eye mask on, and go to sleep....again, won't be disturbed.