You have a sheet and you want to put a space after each character. For example, A1 contains 12345, you want to make it 1 2 3 4 5. B1 contains Mango12 and you want to make it M a n g o 1 2. The same need to be accomplished by a simple macro. (Flash Fill also works in most of the cases. But Flash Fill will copy in a different range which you will have to copy back and if data is scattered throughout the sheet, it may not be convenient)

1. Make a backup of your workbook.
2. Open your workbook and ALT+F11
3. Locate your Workbook name in Project Explorer Window
4. Right click on your workbook name > Insert > Module
5. Copy paste the Macro code given and change "Sheet1" as per your requirement.
6. Go back to your Workbook and ALT+F8 to display Macro Window
7. Run your Macro from here
8. Delete you Macro if the Macro was needed to be run only once.
9. Otherwise save your file as .xlsm if you intend to reuse Macro again.