What changes are needed for wearing.

When your young its much easier as no-one expects someone young to lose their hair, so thick modern hairstyles won't raise any suspicion but as we get older that will change.

I think you can't really generalize as everyone's circumstances are different. How much you've lost/how much you've greyed etc...

But.

1. Thin the piece.
2. Add grey.
3. Show recession more.
4. Appropriate hair style.

Are the obvious changes.

Personally speaking family history is something to take into consideration too.

My father is in his 70's and has great hair. So no-one (family/friends) will expect me to lose mine (that's just how the majority see hair loss). If your father was bald at 50 people might start to expect something if you have a full head of hair at that age, although I guess it's pretty easy to dismiss by stating the bald gene missed me, I've had work done, I'm on Propecia etc....

My hairloss seems pretty slow, I wear the same size hairline piece that I did when I started wearing it 8 years ago. I hope that I get some of my fathers hair gene's and so the hair I have remains and it remains thick.

I would be intereted in hearing how people have changed their piece as they've aged.