Start with the information you have
A new clothing project may begin with one reference photograph and an idea. That is a useful starting point, but a quotation and sample need more specific information. The objective is not an elaborate presentation: it is a clear description of the important requirements.
Explain the product, intended customer and wearing season. Reference images communicate style, but identify which features to keep and which to change. Otherwise, buyer and supplier may interpret the same reference differently.
Break the design into confirmable details
Include front and back views, fabric direction, colors, measurements and decoration requirements. A measurement diagram should show where each dimension starts and ends and identify the units. A chest figure can be misunderstood if it does not distinguish flat width from circumference.
Print or embroidery needs artwork, dimensions and placement. Labels and packaging need content, size and assembly instructions. Mark unresolved details for discussion rather than filling the brief with guessed values.
Quantity and timing are part of the brief
State the total quantity and the breakdown by style, color and size. Give the requested delivery date and destination, and explain any internal sample-review steps. These details help frame the discussion about materials and production arrangements.
As development progresses, combine decisions into a technical pack with a version date. Keep revisions out of scattered messages by recording them in one place. The final documents, approved sample and purchase order should describe the same product so design, purchasing and production share one reference.