Today,I learned about knitting cables. Now that I am home from class and attempted to do it…I goofed it up. How do you Tink or Unknit a cable?
Usually you tink one stitch at a time, but with a cable you take all the stitches involved in the cable off the needle, pull the yarn until the stitches release, then you can see the stitch loops to put them back on the left needle. If you get them back on the needle and notice some are not sitting on the needle in the right orientation slip the stitches over to the right needle until you get to the ones that are backwards and fix them then put the ones on the right needle back on the left needle and try again. So if the cable is over 6 stitches take all 6 off and put them back on the left needle properly. (that’s how I do it at least) 
Does that help?
What she said, but as an additional hint…if you have a cable needle or a big tapestry needle handy, you can put the misplaced cable stitches on that. If you were supposed to, say, slip three to the cable needle held behind the work and knit three, and you slipped three and held them in front instead…not that I’ve ever done such a thing maybe 46,000 times 
…even if you don’t usually use a cable needle, having one or a substitute handy makes it a lot easier to get things back where they belong.
You can also run a tapestry needle or cable needle or whatever through the stitches on the row below where you made the mistake, then pull out the wrong ones. If you’re working on slick yarn or it’s really tight, that helps keep them from escaping sometimes.