If it's just a casual conversation, I would say あなた も 良い 1日 を ね。 (anata mo yoi ichinichi wo ne) or in case if you should be more polite, あなたも どうぞ よい 一日を。 ( anata mo douzo yoi ichiniti wo) the key point is "mo" means "too" hope it helps:)

have a nice day to you : すてきな１日を/いってらっしゃい , too : ～も have a nice day to you ,too : (あなたも/君も)すてきな１にちを Good luck :)

今日一日良い日でありますように "kyouichi nichi yoi nichi dearimasuyouni." Which means something in the line of: I hope today become an all long good day. But, yes, Japanese don't use this term very much.