I already did this in an old excel worksheet but I CAN'T remember HOW I DID IT.

The result is a (plus) + and a (minus) - sign at the top of the worksheet in
row 1 at the location where you want your selected columns to either expand
or collapse.

I need to once again implement this handy formatting trick but for the life
of me remember how I did it....so frustrating!

Anyone out ther know how to do this?