I'd go to that spot where the person is lingering and verbally tell them they are dead. They may not know.
You don't have to be a medium or a psychic to be able to communicate with the dead. They can hear you just fine. Tell them there is a wonderous life awaiting them on the other side. Some instruct them to go to the light.
Say a prayer for his guides and angels to escort him 'home'. That should cover all the bases.
If you hit rock bottom, start picking up rocks.
By embracing my imperfections I am becoming perfect.