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You don't need to start smaller project-wise as long as you take your time. Character design shouldn't take you less than a month. Make references of your own characters for yourself. Here's one of mine:
THe project will very very frustrating if you aren't able to consistency draw a character in different poses.
Then take your time with the storyboard and thumbnails. It will probably be easier to have the whole story down in thumbnails before you begin the actual pages. Otherwise you could write yourself into a very tight corner.