Also, you need to introduce the crate gradually - just forcing him into a cage and making him stay there is going to be a frightening, miserable experience, and he will not learn to like being crated. Make it something he wants to do...coax him in gradually, don't force him. Give him treats/praise, etc. If you play fetch, maybe throw the toy in the back of it so he learns to go in by himself to get it without being scared. Patience, patience, patience. My dog was about 3 years old when I introduced it, and she was ok with it after a couple months.