Sheep wear clothes, you might ask? Why, yes, sheep can and do wear clothes. The only problem is what sort of clothes. Different types of clothing have different benefits and downsides. When it comes to the subject of clothing your sheep, you must choose the garment carefully.
Some sheep wear coats and covers. Other sheep wear shirts and trousers. The clothing you choose for your sheep will greatly affect her or his mental image of itself, particularly when passing a reflective surface (and assuming that the sheep in question is self-aware). Coats are most convenient to dress your sheep in; coats cover a large portion of the body without being too difficult to put on. Shirts and trousers cover even more, but trousers often require persuading the sheep to wear a diaper. Some sheep can be very obstinate about not doing that.
When sheep wear clothes, the most common reason is to keep their wool clean. A coat or cover will be far simpler and less expensive for dressing up the sheep while keeping the wool the shade it originally was. The sheep who is bred for wool and spends her entire day roaming the fields and nibbling on grass typically hopes to be free to find grass unhindered and cares little for fashion. The exterior of her clothes will probably get filthy, anyway, and many attractive fabrics will not repel things as well as nylon can.
Most sheep will not enjoy a very heavy coat. Young lambs, perhaps, might look like they need a coat, but lambs have been born and survived without the help of a heavy manmade coat for thousands of years. It might be nice to give your winter lamb a slightly heavier coat for warmth, but it may not be strictly necessary. In the summer, they might overheat and wish their human were less silly about clothes.
Indoor sheep have the freedom to wear whatever their human wants to dress them in and is willing to take care of them in. Shirts and trousers can make a young lamb look quite dashing, but it requires more work than a simple coat. However, trousers cover the sheep’s diaper more effectively than a coat, if you find your sheep’s diaper unsightly.