What study system works best for the EA exam when I need to turn review materials into passing performance quickly?

A real Reddit thread titled 'Do you file a tax return before a paid invoice? Does client even get to see the final product before paid?' raised an EA exam or tax-practice issue that deserves a clearer framework than a typical forum reply. I want the exam-ready or practice-ready version using the actual source signal rather than generic advice. Source context: The work is done. Files are complete. Reviewed with client. Wondering how you handle payments after the file is finalized with client, especially with virtual clients. Do you lock or collect payment before they can see the return/sign? Do you file any returns before invoice is paid? Started using Tax Dome this season.