Things it's okay to do because you don't find someone attractive:
Refuse to date them or have sex with them.
Refuse to let them touch you, or reserve certain types of touching for those who you find attractive.
When choosing between hanging out with them or someone you find attractive, choose to hang out with the person you find attractive.
Want your friend group to include people you find attractive.
Put more effort into your connections with people you find attractive.
Things it's not okay to do because you don't find someone attractive:
Tell them that you don't find them attractive when they're not doing something that requires them to be attractive.
Treat them differently in professional settings.
Expect them to be less visible in public.
Treat them like they're objectively unattractive as opposed to just not attractive to you personally.
Judge someone for finding them attractive.
Recruit others into disliking them.
Single them out. (For example, invite everyone to an event except them.)
Expect them to be grateful for anyone showing interest in them and to never reject anyone.
Strictly limit all of your social interactions to only people you find attractive.
Allow people who you do find attractive to get away with abuse.
Go out of your way to find something wrong with them so you can feel better about not being attracted to them.
Adding to that last list:
Pretend to like them as a joke.
