Choose a common element
A repeated shoulder line, cap shape or finish can connect a family of different pack sizes. Start with the pack your customer uses most, then develop the supporting pieces.
Compare in context
Review the whole range together. A color that works on a small jar may look different on a tall bottle. Compare physical samples under the lighting used in your retail and photography environments.
Keep the brief precise
Include color references, artwork, intended contents and the quantities for each item. Treat visual references as a direction, with final specifications agreed separately.