Dyed Hair: only for women and only natural hair colors; men when they go gray should stay gray and when men go bald they should stay bald...no dying hair or wigs for men. For any man to do either is a sign of a lack of masculinity and or humility when it comes to aging gracefully.

Piercings (other than earlobes) - not for women and men shouldn't have any at all.

Tattoos - only for certain men who have been in the military (e.g. a navy man or a marine who wants a tattoo related to his service) or a biker-type of guy or mere laborer. For any other man to have tattoos is unnecessary and projects a "trashy image." Ask yourself: would you trust any man to do a very important white-collar job for you (e.g. prepare your taxes or manage your investments) if he had any visible tattoos? Of course not. You would be a fool to do so. Would you trust them to do activities such as bag your groceries, wash your car, put a new roof on your house etc. If he haf any visible tattoos? Of course. Good luck trying to find anyone today to do those things for you who doesn't have at least one visible tattoo.

Tattoos on women? Never. They never belonged on women in the first place and for any woman to have any tattoo (e.g. even a small one on their ankle etc. which she thinks is "cute") is akin to putting a bunch of bumper stickers on a Ferrari or keying a prized automobile. In other words, it's completely trashy no matter what and it totally degrades the woman who has them.

No self-respecting man should ever even date (let alone marry) any woman with any tattoos.

If someone was foolish in youth or pre-conversion, these days, it’s quite understandable. We should refrain from condemning the person until we get to know them. In general, Catholics should refrain from extreme and bizarre appearances out of a desire for humility. Those who do these things, at the time, demonstrate their wanting to stand out and make a statement of some sort, be it, “I’m a tough guy,” or “I’m proud to announce I’m LGBTQ.” 
Most often, it actually reflects insecurity. “I WANT to be seen as a tough guy.” “I’m upset and confused about my sɛҳuąƖity. ACCEPT, no, CELEBRATE my chosen identity.” 
In a few instances, these things are cultural, not any type of desire to stand out.

As Matthew says, hair can grow back, be cut, or restyled. Hair dye depending upon the type, can be washed out, wear off, out grown, or colored over in a more natural tone. Piercings usually close up. Tattoos can be covered with clothing. If not reasonable, can sometimes be removed or even re-tattooed to fade or blend more with natural skin tone. One can sometimes use makeup to cover them.

Many of these things would fall, imo, into the category of making reasonable adjustments out of respect for God, others, self. Unless the person is someone over whom we have considerable influence, it is best to MYOB.

In very extreme cases, like someone with a split tongue and tattoo of Satan on his face, or a person whose body art is immodest, blasphemous, the priest should handle the matter.

Didn't mean to post this as Anonymous...

Well said!
As a former co-worker and I discussed years ago...the time is coming where those without tattoos will be the "odd ones"...are we there yet?

those without tattoos will be the "odd ones"...are we there yet?