I was a would-be superhero who had just learned how to fly. Having acquired this skill, I decided to fly to China for training, because all the great heroes get trained there by mystics. The ground conveniently looked like a world map including black-lined borders, so China was easy to find.
I made my way to the training center, where I had to fill out a little card with basic personal information in order to register for mystic training. There were a large number of other new heroes registering at the same time, and I suddenly realized that they all looked like me (but not, incidentally, like me in real life). It turned out that all the possible timelines merged right then and there, so that every conceivable version of me showed up there together.
Some of them knew how to fly, some could only glide, some could just run really fast, some had other super powers, and some had no powers at all. Many of them were very similar because they had made only a few minor decisions differently, but some were extremely different. One was dressed in dirty, worn-out clothes, talked gibberish and was illiterate. The most powerful hero who had made all the best decisions filled out his card for him, but he ended up being locked in a padded room for his own safety. The mystics said he had made all bad decisions his whole life.
After we got registered, there really wasn't any training to do; instead we used the training center, which was now in a big city in the U.S., as a base of operations for doing hero work. At this point my mind started jumping from hero to hero; in each one I would control maybe thirty seconds of activity before jumping to the next one. Usually it involved flying or running toward some destination. The ones without superpowers stayed in the base and coordinated efforts, answering the telephones and dispatching heroes and such.
