DAAD is the German Academic Exchange Service, and Pakistani applicants routinely speak about a DAAD scholarship as though it were a single award. It is not. It is a large catalogue of programmes with distinct eligibility rules, target groups, deadlines, and application routes.
The single most common failure is applying to a programme whose target group you do not belong to. That is not a competitive loss. It is an eligibility screen, and it happens before anyone reads your essay.
Finding the right programme
DAAD maintains a searchable database of funding programmes filterable by status, country of origin, subject, and purpose. Start there rather than with a general search, and read the target group definition literally.
Development-related postgraduate courses, research grants, and study scholarships for graduates are different things with different requirements, including in several cases a minimum period of professional experience.
What the application asks for
Typically a full academic record, a detailed curriculum vitae in the requested format, a motivation letter tied to the specific programme, references, and often a study or research plan. Where research is involved, a supervisor's expression of interest strengthens the file considerably.
The formatting instructions are not decorative. Files that ignore the prescribed structure are harder to score and score worse.
German language
Many DAAD-supported programmes are taught in English, and some include a funded German course before the programme begins. Do not assume German is required, and do not assume it is unnecessary, because it varies by programme.
Where German is required, the certificate is an eligibility condition and cannot be arranged late.
Timing
Deadlines are fixed and frequently fall a year ahead of the intake. References and supervisor letters are the parts outside your control, so request them early and give the referee the material they need to write specifically.
An application assembled in the final fortnight reads like one.