L.P.
Create a "reward chart" where at the begining of the week, he chooses a special reward, treat, or event that will be his if he stays in bed for 5 days in a row. He needs to understand that he does not get the reward if he gets out even once. I would buy something and show it to my kids, then put it away until they completed the chart. It had to be something they really wanted and a few times I actually took it back to the store in front of them because they didn't follow thru. That did the trick.