Colour coding of wires on USB connector
Beyond red and black (and even then not all the time - sometimes black is hot and not ground) there are no standards. If it's cheap USB cable you are not even guaranteed the same coding between batches - the machine that makes the cable doesn't care what colour is in spool #2.

If you are buying a USB cable and cutting the B end off, your options are limited to getting a multimeter and checking the continuity. Every time. 

Electronics supply shops just might have breakout cables available - A-connector on one end, red and black tinned leads on the other, ready for assembly.