Tools, Macro, Record new macro
Store Macro In Personal Macro Workbook
type something in a cell
stop recording
That will create a macro in Personal.xls, if Personal.xls does not exist then it will be created (and saved when you quit Excel).
Now, Tools, Macro, Macros select the macro then click Step into.
This opens the visual basic editor at the macro you have selected.
Rather than stepping through the code line by line just click the stop button.
Now you can copy and paste Meeko's code into the workbook and delete the macro you just created.
Assuming you want it to act on the currently selected cells then delete the line:
Range("A1:A100").Select