In Celtx, the moment you open a script file it's ready to go. No adjusting margins or setting up tab points; no need to worry about capitalization. Just type, enter, move on...
SCENEHEADING: Every script starts with a scene heading (or Slug line). And our system remembers scenes, so if it looks like you're typing the same scene again, you'll get an autofill option. You'll also notice each scene heading will appear in your navigator, creating a link to that scene.
ACTION: Hit enter after your scene heading and you're typing action. Hit enter again for another paragraph.
CHARACTER: Hit TAB at the beginning of an Action line and you'll switch to character. Again, autofill is your friend!
DIALOGUE: After entering the character's name, ENTER will bring you to dialogue.
PARENTHETICAL: Want to add parentheticals? Just hit TAB when in dialogue. After hitting enter you'll be taken back to dialogue.
Just keep going, enter will skip you through the main formats, tab will let you use parentheticals, text, and transitions.
Or you can use the selection drop down or quick keys displayed in the top toolbar of your script.