Okay, if you already have an inspiration and you want to write it down, that's great. But never try and force your mind into doing something creative. That won't ever work. Never, never, never.
Anyway, if you want to begin a book...I usually do something like an explanation or a flashback so the reader knows what the heck is going on. Or just jump right in. Whatever you have in your head is good. One thing I use (sometimes) is go straight to a big battle to get the reader hyped up, then I make them say "Hang on, this is getting confusing. Let's start from the beginning." Or whatever.
But, use your first chapters to really set your characters, whether they're main or not. These guys will most likely stay for a big majority of your book, so you've gotta set a general "mood" for them. This should be your top priority when beginning.
ANOTHER THING: if the world in your book is complicated or intricate, DON'T DUMP IT ALL ON THE READER IN THE VERY BEGINNING. Always explain it on the way. I'm serious. If there are too many rules and cultures and customs in the beginning, it gets super boring really quickly and you won't get any reads. And rereading it will make you fall asleep.
Okay, these chapters are gonna be really short if this is all I'm gonna do. Also, if I'm making something confusing, please comment on it. I don't want anybody to read this then make a crappy book. Please. Tell me.

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How I Write
AcakDo you have trouble writing books? Ever have writers block? Do you have an idea but don't know how to portray it? Well, this'll help you.