Before adding these custom buttons, you should create your own personal add-in. Don't worry, this is a piece of cake.

1. Open up a new workbook.
2. Start up VBA. (Press Alt+F11)
3. Insert a new module. (Insert > Module)
4. Copy and paste the VBA code into the module.
5. (Take note of what the macro is called).
6. Get out of VBA. (Press Alt+Q)
7. Save your workbook as an addin (.xla) file, calling it something like My_Addin.xla
8. Exit out of Excel, then start it up again.
9. Enable your new addin (Go to Tools -> Add-Ins and select your new addin).

Creating a new macro button in a toolbar.

1. Go to Tools -> Customize
2. In the Commands tab, click on the Macros category.
3. Copy (drag and drop) the Custom Button to one of your toolbars.
4. Right-click on the button and select Default Style to display only the image.
5. Copy and paste the button image as described above.
6. Right-click on the button and select Assign Macro ...
7. Type the exact name of the macro and select OK