Here is a view of the 'loops' that you would normally insert your hook under both to do your single/half double or double crochet.
Again, normal back and forth crocheting you insert under both 'loops'. There is a front loop and a back loop. The front loop is the one closest to the table and the back loop is the one closest to the point of the hook.
My version of the hat uses the back loop only. I always use both loops on my turning/end part to keep it looking tighter and neater. Make sure that when you finish your hat you stitch it together using the same back loops only so you don't have a visible seam.
Let me know if you need further instructions. Good Luck and send me a picture when you're finished!