It usually finds them. On camcorders in my later teens. I started shooting things on film. Writing is the key. When you write your own material you hold all the cards.
All ammunition comes from the script.
P.S. Watch all of Alexander McKendrick's movies. I have a sweet spot in my heart for it. But I'll reach for Boogie Nights any day of the week. It was relatively painless because while I was writing I could call up to the actors who were my friends in the film and make sure that they could clear their schedules for my projected finish date on the script. I'll be watching a lot more Billy Wilder in my time off.