How to downgrade iOS 9.1 to 8.3 on iPhone 5?

I've installed iOS 9.1 on my iPhone 5 and I don't like it at all. I don't like the way you scroll through tasks, I don't like that when I charge the phone the battery indicator remains unchanged until some random amount of time has passed then it suddenly updates, I don't like the the iPhone suddenly goes dark, as though it's battery were removed, yet Siri continues to work and then, just as suddenly, it starts working again and I don't like that apps that never crashed before are now crashing (and they have all been updated to the most recent versions). I want out. How to fall back to iOS 8.3?