hey bro, there are a lot of different things out there and most of them will work well. i have done just about all of them from the hat looking thing, wrestlers bridges, using plates as stated above, and i found that something much more simple works best. all i do is lay on a bench with my head hanging over, let your head fall all the way down then bring it back up until your chin just about touches your chest, just be sure to keep tension on your neck so don't go up to far. go slow and do for three sets to failure, turn to both sides and do the same for each side and backwards as well. when i was fighting i did this every day but i am sure you will get good results if you do it like three times a week. it always worked great for me and got my neck to 22in, so give it a try! hope you can understand what i am trying to say, if not let me know and i will try to be a little more clear. good luck!