Begin your short story close to the end. This cuts your journey in half and makes your story a SHORT story.
Focus on one SCENE at a time! Make each scene as strong as possible.
CONFLICT CREATES STORY. Put your character in a tough situation and have them get out of it in a fun, smart, entertaining way.
SURPRISES (and plot twists) are effective, only when they make sense.
Use strong VERBS. Stay away from adverbs (quickly, sarcastically, flatly, happily, joyously, apologetically, YUCK!). Adverbs slow and interrupt narrative; they also weaken your writing.
USE RECURRING ELEMENTS. If your character wears a silver heart necklace, you should mention it more than once. This makes the world you've created more complete. It's okay to repeat!
I passed along this bullet point sheet to my creative writing students (7th & 8th graders) this week. Of course, these points can be used when writing more than short stories.
Any more you would like to share? I'll take and use.