Writing for a market (Damon Knight, Creating Short Fiction):

Every market has invisible boundaries that they don’t announce. You need to know where those are, and write something fresh that falls inside them.

The best way to know where the boundaries are is to read the market carefully. If you don’t like what they publish, don’t submit.

Don’t write what you think other people are interested in if it doesn’t interest you. Nobody will be fooled.

You have to stand out as well as fit in. Editors don’t want the same thing they’ve already bought.

Don’t write characters who are not interested in themselves, who are bored, apathetic, self-pitying and passive. If you don’t like the kinds of characters that are traditional for the market, write a variation on them; don’t show your dislike by having the characters hate themselves.

#shortfiction