On my way out, about a dozen years ago, I started combing my hair more or less like this:
It was a scandal and it did not sit well with my elder body. I was told I could not read the WT or give any parts unless I started combing my hair modestly.
There were 3 types of approved haircuts for men in my hall, middle part, side part, slicked back:
That being said, even with the approved hairstyles, your hair couldn't be long enough to cover your ears or extend past the collar of your shirt. And if you slicked it back, your hair couldn't be long enough to extend past your forehead if you were to pull it down over your face.
Somebody came up with these rules back in the 60s and they stuck, even decades past the time when such hairstyles fell out of fashion. All those years I had been sitting there at the hall and only then did it strike me how odd all these men looked wearing one of three pre-approved, old-fashioned hairstyles.
I would have probably gotten thrown out of the hall had I dared grow a beard.