Question

what are the properties that the designers have to consider while designing the swim suit

Answer 1

Swimwear is clothing designed to be worn by people engaging in a water-based activity or water sports, such as swimming, diving and surfing, or sun-orientated activities, such as sun bathing. Different types may be worn by men, women, and children. Swimwear is described by a number of names, some of which are used only in particular locations, including swimsuit, bathing suit, swimming costume, bathing costume, swimming suit, swimmers, swimming togs, bathers, cossie (short for "costume"), or swimming trunks for men, besides others.

Answer 2

The propertiez are
1. Material of swimsuit fabric for eg acrylic, rubber silicion,
2. Elasticity and flexibity of the fabric
3. Aero dynamic design to reduce drag
4. Durability of fabric