Get Started in: Writing Science Fiction and Fantasy (Teach Yourself: Writing)

Decide in advance how many ‘plot coupons’ (to use Nick Lowe’s brilliant coinage) your character must collect before s/he is able to ‘cash in’ the story’s conclusion. Identify what the coupons are, and have your character collect them.

Set a tight deadline, with suitably dire consequences if your protagonist does not meet it. Then find a reason in the story to halve the deadline. Then halve it again.

Readers read for characters and the things that happen to them. Writers, often, write to realize their plot, and use characters to make the plot happen. Revision is when you can shift your emphasis from the latter to the former.