I am an huge advocate of shopping sustainably, which can also mean shopping from your closet or repurposing your already existing clothes without having to purchase new ones.
Another way of encouraging sustainable fashion is by thrifting. My closet consists of 45% thrifted clothes which I hoped to have increased by last year but I still find myself shopping other “fast fashion” brands. However, it is not easy to completely transform your wardrobe to 100% sustainable clothing as it is usually an ongoing process.