use the install command to install

Makefile

@@ -34,9 +34,7 @@ clean:
 	rm -f dwl *.o xdg-shell-protocol.h xdg-shell-protocol.c
 
 install: dwl
-	mkdir -p $(PREFIX)/bin
-	cp -f dwl $(PREFIX)/bin
-	chmod 755 $(PREFIX)/bin/dwl
+	install -D dwl $(PREFIX)/bin/dwl
 
 .DEFAULT_GOAL=dwl
 .PHONY: clean