Instead of throwing away old clothing, you can donate it to different organizations or thrift stores. This can also be said for buying new clothing. Thrift stores are a great sustainable option. There are also apps like Depop and websites like thredUP where you can find recycled clothing. If a piece of clothing is too old/worn out to be donated, you can always use it as a cleaning rag.

Yeah, most people just throw it away when there are people who don't have clothing while we're throwing it away. How could we notify more people about this, so people actually contributed?

I think we should stop buying from shein or zara or things like that. We should start buying clothes from ecological brands or local creator. Thrifting is also a good idea, you can find pretty and cool clothes,and it'll be sustainable.  Moreover it is less expensive. We can also look for upcycling tutorial.