this is a quick demo video - it's no frills, nothing glamorous. the explanation below assumes you have an understanding on the way cables are formed.
eta:i uploaded the video directly to blogger many times but it ate it! hence, a vimeo link instead
and here's how i do it!
please excuse the chippy polish ;)
this is a 'hold stitches to the front'/ left leaning cable twist. i find it easiest to insert the corresponding needle into whatever stitches are on the back first, then insert the other needle into the stitches on the front. for this left leaning that's right needle into back stitches, then left needle into front stitches. the reverse right leaning cable: left needle into back stitches then right needle into front stitches. (for a right leaning twist you hold the stitches to the back.)