Once you've got the beginning, how do you move over that hump of figuring out what to do next. You see all these amazing scenes in your head that you have no idea how their going to tie into the story, and once you conjure up a way, you've phased out of the basic idea of your story. Someone, please help!
One of the best things to do is to "begin at the end." Figure out what the conflict is and what the resolution will be and then "back engineer," from the ending to the beginning. A story or a character has to move through something. Identify what it is they or it is moving through. Remember that the story is about "resolving" something. The resolution is a process. The process moves "forward." The "forward" in the case of a story is the plot.