You can't make it from scratch, you have to talk to thw wizard in the basement of the wizard tower or the Magic shop owner in Varrock to have them transport you to the rune essence mine. You will mine it from there
Nope, sorry. Hair only grows if you don't kill it. Which means don't straighten it or curl it or anything. Eat healthy food and let your hair be natural. It will grow at a natural pace.