If the person is a woman, you can say [anata-wa totemo bijin desu-ne] [anata-wa totemo kirei desu-ne] [anata-wa totemo utukusii desu-ne] If the person is a man, you can say [anata-wa totemo kakko ii desu-ne]

I'm still learning Japanese, too. But I guess you could say, "Anata wa bijin desu ne." "Bijin" means "a beauty" or "a very beautiful woman."

Miftaさんはとても綺麗ですね。