Copy cell value to new cell alongside todays date either daily or with button

Hi basically I track my stocks and shares portfolio in excel bringing in closing prices etc automatically to give me my overall profit/loss. I'm wanting to track the daily profit/loss alongside the date each day so I can look back on previous days profit/loss either using a button or a script that runs once a day.

Example:

Sheet 1

A1 (contains profit/loss total)


Sheet 2

A1 (todays date) A2 (value of sheet 1 A1)...
and then the same the next day etc.

Any help would be much appreciated, I'm new to macros etc so an in depth explanation would be appreciated, thanks