What should one wear in Turkey now? Sweaters ?

The temperature is about the same as Beijing.

First check the weather forecast for Istanbul and dress according to the temperature. For Goreme, it's cool in the morning and evening, so bring a jacket. During the day, wear loose pants. If you're going to a coastal city, it's hot, so wear summer clothes.

Bring a cardigan, it's a bit cold in the morning and evening by the sea, but hot at noon. Locals usually wear short sleeves with a cotton vest.