I like to begin every screenplay with a burst of delusional self-confidence. It tends to fade pretty quickly, but for me, at least, there doesn't seem to be any other way to start writing a script.
Michael ArndtI can write two scripts concurrently, but I usually prefer to do one at a time. However, I also usually have 5 or 6 story ideas that are percolating in my head at any one time, so it can get a little crowded in there.
Michael Arndt