In 1987, I was in Pakistan to climb Gasherbrum II, one of the world’s highest peaks. We were a small group and it was a very big mountain. Our expedition faced more than its share of difficulty: A long storm wiped out most of our food rations and an avalanche devastated our camp, obliterating our tents. One of our party developed altitude sickness; blood poisoning threatened another. In the face of each disaster, we carefully developed a new plan. Snow caves replaced lost tents. Soups replaced full meals. Eventually we climbed slowly to the top, then made our way safely down.
Now go back through that list and cut-and-paste the elements within each subgroup into an appropriate order. When you've finished, read over the entire outline from start to finish. Does it make sense? Is there a reasonable flow? If there are gaps, you may need to go back to your notes or do more research to fill them. If you're having trouble deciding on an order in a subgroup, make it work as best as you can, and it may straighten itself out logically next in the writing phase. If something really doesn't fit, perhaps you should consider removing it from the essay, because perhaps it's unimportant and would just jar the reader.