a) Looking at the pictures:
* Steve & Bill: Steve is wearing a suit. Bill is wearing a jacket and trousers.
* John, Ann, Stuart, Mary: John is wearing a shirt. Ann is wearing a shirt. Stuart is wearing a plaid shirt. Mary is wearing a white t-shirt.
b) As a language model, I don't wear clothes. But I can suggest what someone might wear:
* What are you wearing now? I am wearing a t-shirt and jeans.
* What do you wear when it is cold/warm? When it is cold, I wear a coat, scarf, and gloves. When it is warm, I wear shorts and a t-shirt.