Characters are the core of the story. Without them, you really don’t have much of a story or really anything to write. It’s why I take a lot of care in my character building. I want to understand the character the best I can before I start the story itself. Once I know my characters, the story will unfold from there, and I don’t have to worry about knowing every possible detail about the plot itself. My characters will reveal all the details to me in time, and if I write myself into a corner, often it is character building exercises that help me pull myself out and toss me back into the flow of the tale. To be honest, when I write, this isn’t my story I’m telling, it’s the characters’ stories. When I’m cognizant of that, it makes it a lot easier to write the tale, and to avoid suffering from writer’s block.
To help myself along, here is the general template I use for character building. This template is years in the making, where I’ve received permission to borrow aspects of other writing friend’s templates and some I developed on my own: