Tell him he is going to sleep in his own Bed like the Big Kids do, and at Bedtime Take him to his Room, read him some stories and Tuck him in, leave the room he may yell and say he is scared ,reasure him once that you are near by and he is alright , he wont like it. but consistancy is the Key, if he comes out take him back, no words or admonishments, if you keep this up he will form a habit of staying in his Room .