The most efficient way to design a spreadsheet is to setup the criteria for the report in one area of the spreadsheet, then reference the criteria cells in each function. This allows you to quickly and easily change the spreadsheet for a new accounting period or restaurant, and helps prevent data-entry errors.
You can use absolute cell references, relative cell references, or a combination of the two. The difference between the two types of references relates to whether the cell pointer changes when the cell is copied. An absolute cell reference does not change when copied. A relative cell reference does change when copied.
When entering a function, each cell reference is relative by default. You can select each cell reference within a function and press the F4 key to toggle each part of the reference to be absolute:
The first time you press F4 the entire cell reference becomes absolute
The second time you press F4 the row reference also becomes absolute
The third time you press F4, the column reference also becomes absolute
The fourth time you press F4 the cell reference becomes relative
Then the pattern repeats
You can manually make a cell reference absolute by typing a dollar sign ($) before each part of the cell reference.