A serious Helmut-Schmidt application should not begin in the final week of July. The safest plan is to spend the first days confirming course fit, the next stage collecting documents, and the final stage checking forms, signatures, translations and uploads. If you need an English test or official translation, start even earlier.
The first week should be used for source checking. Open DAAD, save the official call, and read every participating course page you are considering. By the end of that week, remove courses that do not match your academic background, work evidence or language proof.
The middle period should be used for documents and writing. Request work letters, scan academic records, prepare translations, draft the motivation letter and check whether course-specific forms are required. Do not wait for the motivation letter to be perfect before requesting documents; these tasks should run in parallel.
The final week should be only for quality control. If you are still choosing courses, requesting certificates or learning the portal in the final week, the risk of avoidable mistakes becomes high. A polished application is usually the result of calm preparation, not last-day pressure.