i feel like ardra (particularly in the moon) can be a nakshatra that can spiral pretty easily and even terribly if it's not controlled/disciplined enough (ex. impulsively getting tattoos they might regret later on, negative/suicidal thought forms -> actions, alcoholism, etc.) but there should be ardras out there that have this under control. if you ever want more information about ardras, i would suggest watching simon chokoisky's videos since he open up a document about them while talking: video 1, video 2, video 3
anyways, physical appearance lol...
from the ardra moon men that i mentioned before, i don't think i've noticed a consistent physical similarity…? i also don't really have pics of my paternal grandpa, so i can't say 😅
not sure if you've checked out pinterest before though, but on there, people have made albums and compiled pics of ardra sun/moon/asc male celebrities' appearances if you're interested: album 1, album 2, album 3, album 4, album 5
based on these albums, i guess if i had to briefly list down physical traits of ardra men i see so far: bushy/angry eyebrows, a piercing stare, hair that can be a bit messy/unkempt, may be more prone to a disheveled look in general.
*note: if you're using a common ayanamsa + house system like lahiri whole sign, you may notice that there's at least one non-ardra man incorrectly placed in one of those albums (ex. kanye west) so if there's a guy that intrigues you, be sure to double check!
anyways, besides that... fashion wise, i keep seeing people pin ardra nakshatra to grunge, but i also feel like i see ardra natives in comfy/casual skater/streetwear type of fashion. think beanies, oversized hoodies, oversized bomber jackets, baggy pants, ripped jeans, acid wash/bleached denim, etc. their fashion could also be from or inspired by animal products like leather and fur/sherpa due to ardra's ruling deity being rudra (which is a form of shiva) and is depicted wearing animal pelts and a snake wrapped around his neck.
keep in mind these are just generalizations/tendencies i've seen so far and all/not everything will apply.