How to thicken your hair?

Ok so i got really thin, straight hair. I must say i did straighten it for like 3 years straight every morning which i know is extremly bad for your hair... But its super thin, and also used to break alot. I switched conditioner to something that treats breakage, and the breaking stopped. But my hair is still very thin, and i cant do much with it. Im wanting to get the scene/emo hair cut, and im sure you have to have thick hair... so i need to thicken it... any suggestions?