How to Make a Formula in Excel

Simple Math Formulas
1. Open Microsoft Excel by clicking on your Desktop shortcut or by selecting it from the Windows Start menu. You will automatically get an Excel Workbook. The workbook has three blank worksheets that Excel has named Sheet1, Sheet 2 and Sheet 3.
2. Remember that each column has a title that Excel uses in formulas, and each row has a number. The place in a worksheet where a row and column meet is a cell. Each cell's name is made with a column letter and the row number. The first cell at the top of the worksheet is A1. The next cell to the right is B1.
3. Start typing your numbers that you want to calculate in Sheet 1. You can type the numbers in a single column or you can type them across the rows. You also have the option of typing your data in more than one column or row.
4. Put the cursor in the first empty cell below the data in your column or at the end of your first row. Notice that Excel displays the cursor location and cell name below the toolbars at the top of the screen.
5. Begin every formula by typing the equal sign. Excel immediately displays it in the Formula Bar that is above the worksheet's first row.
6. Click the first cell that you want to include in your formula. Excel adds the cell name to your formula. Type a mathematical function. If you are adding numbers, use the plus sign on your keyboard. For subtraction, use the minus sign. To divide, use the slash on the question mark key. To multiply, Excel uses the asterisk, above the number 8 on the keyboard.
7. Click each cell that you want in your formula, then type the arithmetic function that you need. Click the green check mark at the beginning of the formula bar when your formula is finished.
AutoSum
8. Use Excel's AutoSum button for faster addition of one column or row of numbers. It will be much easier than clicking on each cell and typing the plus sign.
9. Place your cursor in the first empty cell after your numbers. Click the AutoSum button. It resembles a fancy capital letter E and is located on Excel's editing toolbar. Excel highlights all the cells in the column above until it reaches an empty cell. For data in rows, Excel selects data to the left of the cursor.
10. Click the green check mark in the formula bar to complete the formula.
Use Excel Functions in Formulas
11. Make a formula with Excel's built-in mathematical functions by placing your cursor in an empty cell first. Then type the equal sign to start the formula. Choose Formulas, and then choose Insert Function in Excel 2007. In Excel 2003, click to open the Insert menu, then select Function from the drop-down list.
12. Select the function that you want. Your choices include financial, date, time, statistical, engineering, trigonometry, logical and many others, arranged in categories. To see all of the functions, select All in the category drop-down box.
13. Select the function that you need by highlighting it in the function list. Click on it to insert it into your formula. Excel places it in the formula bar. Select the function COUNT or AVERAGE to try this out.
14. Complete your formula by clicking each cell that you want to include in the formula. After you finish adding cells, click the green check mark. Excel displays the results of your function's calculation.