It means "what interesting/fun/good/great things are you doing in life?" The construction faire quelque chose de + adjective in French = "Do something + adjective" in English. So "I am doing something fun" = "je fais quelque chose d'amusant" "He is doing something good" = "Il fait quelque chose de bon" "Que fais-tu de beau?" = "What fun/good/interesting thing(s) are you doing?" Hope this was helpful!