There are two ways to submit Workflow projects: through quick review and by submitting a work request for a project. Read more about submitting a work request in this article.
When you want to quickly send a proof out for review, you can send it through the quick review or drop it into the left navigation. The entire left navigation is a drop zone, allowing you to create projects on the fly and get them moving fast.
To start, just upload a file, select a due date, add a project name and special instructions, then add reviewers. Click "Start routing" when you're done and the proof will be on its way to review.