Often self-harmers wear long sleeved t-shirts to hide their scarred arms or trousers instead of skirts.
Self-harmers harm themselves using; blades, fire, shavers, etc. Anything to relieve the pressure of pain they feel emotionally.
Sexual abuse, bullying or just mental isolation could cause self harm. Many self harmers are pressured into dressing an calling themselves emo so people will understand what is wrong with them...Which then leads to them being labelled attention seekers and feeling worse. It's a vicious cycle.
Self harm can sometimes go beyond cutting arms. I rub hairspray into them after which hurts like hell.
Sometimes self harmers stop before a certain using a cutting implement e.g razor, kitchen knife (but a craft knife seems to be fine...i should know)
Most self harmers are normal people who have suffered and have not "got over it" even if the event happened years ago. They may act manic depressive or paranoid, and have no trust. They act differently around people who they know, pretending to be happy and bubbly, or just very shy...
I'm not emo I just hate myself.