Getting horse into jumping shape?

Lunging is always a great idea, especially over jumps. Hill work would be great for conditioning. Trot and canter poles are very helpful. Start out with small jumps and jump them a couple of times each time you ride him, if you feel comfortable. Be careful not to overdo it or you could injure him. Slowly start increasing number of times you jump and/ or jump height. If he is in shape then he should have no problem jumping, if he knows how to.