Hi all, some questions about growing out

Hi, Im 20 years old and  male.  Ive always had short hair but now i get it cut infrequently it grows slightly shaggy.  ive always been interested in growing my hair long so that the front goes over top of my head and down to my shoulders.  right now its just shaggy all around and eventually just turns into a really ugly bushy mushroom cut (my hair is very thick).  im not sure what to do in order to get it to look nice while its growing out and more importantly get the shape i want it which is basically all my hair behind my ears down to my shoulders (not just long and shaggy all around). thanks in advance

if your hair is very thick perhaps you should get a few layers cut in to it to make it hang better.