Okay, so usually when I start a new story, I like to take out my notebook and start brainstorming my ideas (usually l start with a genre like fantasy, horror, romance, etc...) and then I write down random ideas that I want to incorporate into the story.Try using bullet points, or use this outline:

Genre:_______________________
Plot ideas:
o
o
o
o
o
Character ideas:
o
o
o
o
o
Plot twists:
o
o
o
o
o

THEN
Chapter outline:
Main ideas:
o
o
o
o
o
Characters I want to use in the chapter:
o
o
o
o
o
Detailed ideas:
o
o
o
o
o

ORRR You can use this site:
http://shortstoryideas.herb.me.uk/
http://www.rangen.co.uk/writing/plotgen.php (This one is only good for SOME genres but it's an awesome idea sparker)

Notes