Copying Cells to new row on different worksheet

I am in the process of developing a workbook including charts (Like a
dashboard)where indivdiuals could enter the # of wigits produced today in one
highlighted cell (updated through out the day). Each time they update the
cell with a new number, I want the information copied to a log on a different
worksheet including a date and time stamp for trending purposes.

I am trying to keep the work and time to a minimum and many of the people
who would enter the information are not familiar with Excel. I would like to
simplify it so they can open up the workbook and have a graph showing the
current production status and next to the graph have one cell say A3 where
they would enter the day's new wigit #.

How do I code it so each time they update that cell, it copies the cell's
contents to worksheet #2 at the bottom of all the previous entries?