We have done all the prep work and now it is time to start writing! After all, this is what we want to do, isn't it?
There are many ways to write your story. You can write all those nifty scenes that have been rolling around in your head and then plug them all in with filler, or you can go the direct route and write from beginning to end. This is my preferred style.
However works best for you is fine. As long as you write! Don't get bogged down in planning your sentence structure, editing, looking up fancy new words, creating the "perfect" red herring. Now is just about getting the story down on paper. All that other stuff can be done after you get the story out there.
Work on your story a little bit each day. Don't wait for inspiration to strike. Just get the story out there and then you can go through and revise, edit, and toss out all the "junk". Although writing does happen in inspired moments, those are not the only moments you should be writing.
Someone said that writing is 10% inspiration and 90% perspiration. (Okay, actually, I am pretty sure the quote was by Albert Einstein and wasn't about writing, but the message still remains true!) Force that story out. Nothing worth doing was ever easy. (From a woman who has had a child, believe me that is so true!!!)
Follow the paths that your story takes you, but be sure to keep an eye on your outline so that you don't end up on a tangent that takes you to Timbuktu. At this point, don't focus nearly as much on your writing, just focus on telling your story. It will make it easier to get the story out there. Then you can shine it, polish it and turn that turd into a shiny marble-looking turd. (I know it is gross but yes, this can actually be done. Saw it on Mythbusters.)