How to Add Collapsing Plus Signs in Excel Columns

1. Open the Microsoft Excel 2010 worksheet that holds your data.
2. Click on the column letter above the first column that you want to include in your outline. This will select the entire column. Hold the Shift key, then click on the column letter above the last column you want included in your outline.
3. Select the 'Data' tab at the top of the Excel window. Locate the 'Outline' area of the Ribbon and click the 'Group' button. You will see a line appear above your columns with a minus sign on the end of it.
4. Click on a column letter within your grouped cells, then hold Shift and select another column letter to create a second level of the outline. Click the 'Group' button again and a new line and minus sign will appear under the first one. Continue creating levels until you have created your entire outline, or until you reach eight levels, which is the maximum that Excel will allow.
5. Click the minus signs to hide the levels of columns and all that will remain above the columns headers is a set of plus signs.