If you don't have the crew though, you might be forced to, which sucks but is doable, even if it takes ages longer..Definatly get someone to write with. It does help.
Also it might be helpfull to make a planning if you want the crew/actors to be availible.
If you make a 2 part focus on one at a time. Visit locations before the shoot & don't direct & do camera at the same time. Those are seperate roles!
K thx. I can't wait to see your short film.for screenplay try to avoid dialog if your not to good at it maybe make it more action with one liners. as for the rest ill be personally be doing my first short here soon ill let you know my experience. hope that helped