You say, "color standards are really not followed". Well, that's only partly true.
For THREE-pin fans, almost every fan (yours appears to be an exception) uses the same convention:
Pin #1 - Black - Ground
Pin #2 - Red - +VDC, voltage varying to change fan speed
Pin #3 - Yellow - Speed pulse signal from fan back to mobo header.
Now, FOUR-pin fans do NOT use that set of COlLOURS - in fact, there is one set used most commonly, and a second set used moderately often. Becasue of the difference in fan sype design, the functions of the pins are SLIGHTLY altered.
Pin #1 - Black - Ground (no change)
Pin #2 - Yellow - +12 VDC supply NOT changing
Pin #3 - Green - Speed pulse signal again (same function, different colour)
Pin #4 - Blue - PWM signal from mobo, used by fan chip to control speed
For your purpose, OP, IGNORE the 4-pin system. You have a THREE- pin fan.