How does Superman cut his hair?

Seriously! Is he like a saiyan and it just stays one length forever? Does he have like a pair of kryptonite scissors to cut it and wouldn't the regular exposure eventually weaken his head? He couldn't like rip it out or cut it with his nails or something because that would mean that his hair/scalp is weaker than the rest of him and therefore a vulnerable point that his enemies could exploit. Maybe he uses his laser eyes to cut it, but that would mean his laser eyes could hurt him so all you'd need to defeat him would be a mirror. Man, I'm going to be pondering this for ages now!