Customize Cell Comments
When you insert a cell comment via Review → Comments → NewComment button (pre-2007, Insert → Comment), by default Excel will also insert the username for the PC being used. You can change this by selecting the Office button → Excel Options → Popular (pre-2007, Tools → Options → General; on the Mac, Excel → Preferences → General). The username will appear at the bottom of the dialog box that opens, where you can type whatever you want to be shown by default.
Although cell comments serve the simple purpose of displaying a message to either yourself or another user, you can customize the cell comment so that it better reflects your intentions.
To make this tutorial work, you will need to add the Change Shape button to the Quick Access toolbar. Do this by going to the Office button → Excel Options → Customize. Then, from the Choose Commands From dropdown, select the Smart Art Tools/Format tab. Locate the Change Shape tool, click on it, and then select Add to add to the Quick Access toolbar, followed by OK (pre-2007, you won't be able to add this tool, so ensure that the Drawing toolbar is displayed by selecting View → Toolbars → Drawing).
Insert a cell comment into a cell by selecting the cell, going to the Review tab, and selecting Comments → NewComment (pre-2007, Insert → Comment). This automatically places you in Edit mode, ready to enter text into the comment box.
Left-click the outside border of the cell comment so that you are no longer in Edit mode. With the comment selected, select the Change AutoShape tool from your Quick Access Toolbar (pre-2007, select Drawfrom the Drawing toolbar, then Change AutoShape). You will be presented with a list of options including Basic Shapes, Block Arrow, Flow Chart, Stars and Banners, and Callouts. Choose an option, and the cell comment will change to the shape selected.
If you are using Excel 2007, you will notice that any shape you choose will have a three-dimensional look. If you want to create this look in pre-2007 versions, ensure that your comment is still selected, but that you are no longer in Edit mode. On the Drawing toolbar, click the Shadow Settings icon and choose a shadow setting for the cell comment.
