When using Excel 2010, or earlier versions, there are many times you want to select nonadjacent cells to build a formula or to format individual cells on the worksheet. There are a number of keyboard techniques that allow you numerous options for selecting any cells you want without deselecting cells you have previously selected. Excel has a built-in feature called "Add to Selection" that can be turned on and off with a keyboard shortcut.
Add one cell at a time to previously selected cells, without deselecting any of these previously selected cells, by pressing and holding "Ctrl" while you use the left mouse button to add new cells.
Add a range of cells to previously selected cells without deselecting any of these previously selected cells by pressing and holding "Shift" while you drag the left mouse button to add a new range of cells.
Add more cells to an existing selection of cells by turning on the "Add to Selection" feature by pressing "Shift"+"F8," and then using your mouse to select any nonadjacent cells.
Turn off this "Add to Selection" feature by pressing "Shift"+"F8" a second time, and Excel will revert to the default cell selection technique.
Practice adding cells using the “Ctrl” and “Shift” key techniques, and you will quickly understand how this works.
Try out the “Add to Selection” feature to make this tool part of your Excel toolkit.