To use the AVERAGEIF or AVERAGEIFS functions in Excel follow these steps:

1. Select the cell that you want to place the result.
2. Start a formula entry by typing an equal sign (=).
3. Type the AVERAGEIF or AVERAGEIFS functions with the range of cells containing the data, the criteria that the data must meet, and an optional range/criteria audit.
4. Press Enter and the result will appear in the cell.