Okay first things first, what type of genre do you enjoy writing or want your story to be in? Science fiction, fantasy, romance, horror (my favorite XD)! And we'll go from there.
What I would do though, is to just write. If you can't write anything within what you're currently writing, then try writing something else for a while. As long as you write, you keep your creativity up. The inspiration for your main project might spark up.
If not, maybe you're not passionate enough about it. Move on to a new idea.
"I never saved anything for the swim back."
Do not mistake coincidence for fate. - Mr Eko
they're selling razor blades and mirrors in the street
To have more, you have to become more. Don't wish it was easier - wish you were better. For things to change, you have to change, and for things to get better, you have to get better. — Jim Rohn