Bill King gave a very interesting talk and demonstration of cables. What looked complicated was actually quite simple.

Everything was based on a 3x1 setting.

Knit the welt then transfer every 4th stitch to the adjacent needle. Keep the empty needle in work. Knit to where you want to cable then drop the stitch each side to give more yarn for crossing. Using this method Bill showed what looked like a complicated trellis pattern, but once you know how quite easy.