1.Does it refer to your outfit? It's the other way round. Your outfit is your clothes, plus shoes and any accessories you have. For example, a woman's 'outfit' for a special occasion is her clothes, her shoes, jewellery, hat or hair accessories. 2. Do you use a piece of clothes to refer to a piece of your outfit such as pants, shirts, etc. No, we don't say 'piece'. If you want to refer to one thing, such as a shirt, in the singular, you can't use the word 'clothes'. You can say 'an item of clothing', 'an article of clothing' or a 'garment'. 3. Is it correct to say that you need to take one piece of your clothes? which refers to you can take one piece of what you are wearing, such as pants, or shirts? See answer above. 4. Does clothes refer to shoes? Not usually, but it can do. If you say 'I'm going to wash my clothes today', it's clear that you don't mean shoes. But if you say 'A thief stole all my clothes while I was swimming in the sea', you'd presume that your shoes were probably stolen as well.