I had a boy cut but now it's growing out! and it looks hideous..?

I had the same problem!! The first time I did this I used a lot of cute barrettesand bobby pins to pin my hair in different cute ways. It worked but fortunately I was still in high school. I wouldn't really walk around like that now. The second time I had this problem was about 4 years later... and I just made it look messy until that didn't work anymore. I think I continuously had the back (around my neck area) cleaned up frequently to get away from looking like I had a mullet. It actually was a lot more bearable the second time.