I want to write (and draw) a comic book, but how do I get started? Start with the story, then plan the panels accordingly.
Am I supposed to re-draw the characters each time, or what? Yes, you re-draw the characters each time.
And, how do authors/illustrators get their drawings so damn accurate each time?? They've had lots and lots of practise. My advice is to not start drawing your comic until you've practised enough to consistently draw your characters the right way every time and from every angle. This should save you a lot of time in the end.
There are a lot of tutorials online on how to plan and draw a comic book, so I suggest you read/watch some of these. Again, the more prepared you are before you start, the more time you'll probably save in the end.