Hello Dear Anon :D Thank you so much for liking my OCs (o´艸｀o) ♥♥ Here are some methods I use when lining hair. ( I will put the coloring part in another post since its getting long)
Basically, as long as you have the flow defined, no matter how complicated / sketchy your line is, the flow will frame them in like a mother hen hugging all the babies♥ Also when you add in details or strokes, follow the flow too, Like babies chicks following their mamaヾ(○´▽｀○)ノ
Hope it helps! and hope I explain it alright? If you have any question please do let me know!