I want to do following thing

(1) On day2 when I open excel sheet, data that i entered on day1 in
perticular sheet (say sheet1) should be hidden automatically.
Or
(2) On day2, when I open excel sheet & enter today's date on sheet1,
data entered on day1 should go hidden.

i want to do this daily basis.
Pls also tell me how to unhide this.

thank you