Is this correct?
I wanted to know what 'How's your day' and I found this so is this correct?: あなたの一日はどうですか
「 あなたの一日はどうですか」 would be a literal translation. Of course it is grammatically correct and enough acceptable, but rarely used in daily conversation.
An idiomatic translation would be just「今日はどうですか」 or something else. When someone asks a question to another person, the second-person pronoun is often omitted in Japanese, for euphemistic expression and courtesy. Namely, 「今日はどうですか」 is more common than 「あなたは今日はどうですか」.