If you or your employees do not know how to use Excel, the first thing you should learn is to entering data into a cell. It may seem obvious to you but we do find a number of people learning the wrong way when it comes to entering data into a cell. The wrong way is to double click on the cell or clicking on the formula bar before entering the data. The right way is to just select the cell you wish to enter the data in and just type. When completed, confirm the entry by hitting the ENTER key. DO NOT click another cell to confirm the entry. You will find yourself not able to perform special entries when you confirm the entry using the wrong way.
Next you should learn is cell formatting i.e.
1) Number Formatting
2) Font Formatting
3) Border Formatting
4) Fill or Cell Colour Formatting