This can easily be done in `Local Multiplay`
Create a single hole (which will net you the `Budding designer` achievement if not already done.)
Select Multiplayer - Local Multiplayer
Scroll across course till custom is selected
same again with theme
when on the holes option press X to add your selected hole
press a to continue
Add a second player on another controller
now on your main profile character press Y to customise character - I altered every option to be on the safe side
Ready up and play - making sure the main profile wins (of course)
Rinse and repeat for the 3 remaining characters and pop goes the achievement
Takes a matter of minutes to do.
Hope this helps some of you out there