Read the script once from beginning to end, as if you are seeing the movie. Don’t stop to take notes or breaks. Take a breath when you finish and then write everything you felt and remember. These are your initial notes.
Read the script a second time, this time making notes in the margins as you go. You want to remember what works and what doesn’t.
Organize your coverage with a cover page comprised of the following parts: A table with the script title and author, the page count, the genre, the location, the budget range, the time period, the date submitted and your name. You'll also need a logline--a three sentence or less telling of the story; and a chart which includes your assessment of the script relating to Premise, Story Line, Structure, Characterization and Dialogue on an Excellent, Good, Fair, Poor rating scale.
Follow the cover page with supplemental pages. You will need a Synopsis (could be 1 to 3 pages), Comments (anything from structure to marketing to overall impact), and Recommendation (buy it now, have it rewritten, pass on it). A reader is sometimes smarter than the screenwriter and can write better as well. On the other hand, a great screenplay reviewed by a dumb reader will seem like a hopeless mess. Good executives are often made by good readers.
Proof your coverage. Make sure it is your best writing. Remember that the document you write might sell the script to a studio and might very well make people other than you rich and famous.