what flag colors are used to determine pin location at Augusta and what position does each color designate?

Answer 1

They do not use flag colors at Augusta. It is a very private club and the members (and guests) are given a card that indicates the pin locations for that day.

Answer 2

Augusta uses a pin placement sheet that indicates the pin locations for the specific day. Many other course do use colored flags to indicate the relative pin location. Relative to the center. Red being front, white middle and blue back, pretty much the same way the tees are layed out. Some golf course do substitute yellow for the whit or Red flags. This is at their discretion as there is no specific rule.