I have to start writing a story in my head before I can begin typing otherwise I'll just be shut down by blank paper syndrome. If you're like me then you should maybe choose one idea for now, get really into it, go to bed and start imagining everything, describing everything in words. Rearrange those words, find a good place to start, and run through your narration several times in your head before moving on.
I found when taking a writing workshop that if I had a sentence handed to me as a jumpstart, the story could just spring off of that no problem. It just gets tricky when you have to write the first sentence yourself