Tips on cutting emo layers??

Ok so 15 yr old guy here, I've been dressing more emo/scene the past few years but haven't got full emo hair yet :( my hair rn is pretty long and more metalheadish but I wanna get the classic emo look. Don't trust any hairdressers in my area or myself not 2 mess the layers up D: help!!! Any tips on how 2 cut them myself appreciated!