Find a quiet place to write. Have a deck of index cards and a writing instrument nearby. Play your screenplay story in your head, over and over if necessary.
As you see a scene or plot sequence unfold, write a description on an index card. The description should be key words at minimum, one or two sentences at maximum. While brevity is necessary in each part of a plot outline, at the first draft stage of this technique, it's okay to wind up with as many plotting cards in your deck as you desire. At the first draft of a plot outline, the looser you are the better the results. You can always toss out cards in subsequent drafts.
Once you reach a point where you're satisfied with the structure that you've created, spread all the cards in the deck across a table for an immediate visual assessment of your screenplay's timing and scene interaction. If you don't like the results, reassemble the deck and revise as needed.
Once you feel satisfied with the table assessment, start writing scenes. Don't throw your deck of cards away because, rewriting is a natural part of the writing process, and you may have to go back to your deck to reshuffle and revise your plot structure.