Well it's all up to you, take some time looking in a mirror, see how you can imagine a nostril piercing. Here's a tip, take a stick on clear gem stone and place it on your nose where you want the...
It's a fashion statement and some people like it (like tattoos) while others don't. Some younger people will choose to follow what their peers do. It's a phase and they'll grow out of it....
It depends what you want done. To get your nose done you have to be 12. To get the bottom of your ears pierced you can be any age because I gpt it done when I was like 6 months.