put some treats in there for him but leave the cage door open. hopefully he will go in to get them. dont shut the cage door though... let him go in and out without having to stay in there. then you can move up to keeping him in their for small amouts of time like 5 min while your home, and longer times and longer, until at last you can leave him there a while you leave or when you need to. you also may want to put the crate in the part of the house you spend the most time in, so he still feels like part of the family when he is in it. good luck