Tab over to "Advanced Techniques" on this site and scroll down to "Small Diameter Circular Knitting" and look at the two circular needles method. There is nothing, repeat nothing, that works as well to eliminate ladders as switching to 2 circs. The reason is not only because you only have two needles instead of 3 or 4 but also you can tighten the yarn from the last stitch on one needle on the cable thereby making it smaller than a normal stitch. Then when you inevitably stretch the yarn to switch to the other needle, it evens out and becomes invisible.
I did my first pair of socks on dpns and was very disappointed in the ladders. I had tried all the techniques to minimize them also. Then I did a pair on 2 circs and no ladders!