Formal:
* Tumhaar diwas kyaa tha? (تُمہار دیوس کیا تھا؟) - This is a more formal way to ask, directly translating to "How was your day?"
Informal:
* Aapnaa diwas kyaa rahaa? (آپنا دیوس کیا رہا؟) - This is a more casual and friendly way to ask, meaning "How was your day?"
You can choose the appropriate form depending on who you are talking to and the situation.