If you would like to litter train your rabbit here is how you can do it. Bring rabbit into the house and sit it in a litter tray lined with kitchen roll and hay. Try putting in a few of the rabbits droppings or newspaper soaked in its urine so he/she can smell it. he will recongise his own urine smell and hopefully use the tray. Some times rabbits tend to prefer a different corner to go to toilet, try placing the tray in the spot where he/she is using.