just scrunch them up and either tape them together, ot use cable ties. But apart from that don't split the ribbon cable into individual strands, becuase the ground wires are important, and must be kept in between the signal wires to stop cross-talk.

Think about it: if you have to keep the ground wires between the others to stop crosstalk, then scrunching them up will make wires next to each other without ground wires. I do not recommend you do this with SCSI cables, you may be able to get away with it with Wide SCSI or some of the other older ones, but I wouldn't bother. If, however, you do want to try it, don't buy them online, it takes about 7 seconds to use three cable ties to scrunch them up.
-Mike

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