If needing to stop for a between-control nap, leave your bike pointing in the direction you want to travel when you wake up. If you need to know why this is a good idea, ask Salvatore. He will also be able to provide you with a description of the literal meaning of deja vue.
There’s another tip for similar circumstances when you want to avoid fellow well-meaning randonneurs stopping to check you’re OK, usually by waking you up. But I can’t remember what it is. I think it’s some sort of convention relating to lights but if so, it depends on everyone knowing the convention. It may be safer to carry a ‘Do not disturb’ sign in the saddle bag and to deploy it when necessary.