To make a naga fly, you would either need exceptionally wide wings which extended down the tail, or else rely on multiple pairs of wings distributed down the body.
I myself am not too big on the idea of nagas capable of outright flight. It just doesn't seem to fit together properly. A naga goddess might have an excuse, but biologicially speaking, snakes aren't built for flight. An aerial naga would be a VERY specific design, most likely with a reduced tail and exceptionally wide wings. It would make more sense for such a creature to walk on its wings, rather than its tail.