To tell you how to use swing needles when knitting, I could go on and on.  I am not good at describing how to do techniques because I’m left handed and do everything backwards.  I do know of a link that explains this process using two balls of yarn, clearly and concisely.  http://www.lismoresheepfarmwoolshop.com/needles/instructions.htm  I don’t think that you can find a better explanation then this, except in a knitting book, and those are often, well sometimes very vague and use terminology that I  find unfamiliar.  If this is not what you are looking for, simply type the words, "swing needles for knitting" in your search engine.  You will be surprised how many responses pop up.  It’s nice to know that people are knitting again.  This kind of activity is a great stress reliever.