The Nova Studio over two years ago, I have always enjoyed seeing other soap makers versions of swirling soap. If you want to learn how to make swirl soap, I found these great instructions for In the Pot Soap Swirl Technique from Inner Earth Soaps. Inner Earth Soaps provides some really good tips on this technique that are really helpful.
So if have never made swirled cold process soap, you should give it a try! I have seen other soapmakers have six colors or more. I think that is alittle bit too much and it would be very difficult if it was your first time trying this technique. I would say start with two colors. Once you master two then try three. I really like to keep things simple. You know that saying "Less is More".I think three is the maximum number for me. If I were to do three, I would try two primiary colors like red and blue. If they combine that would make purple. But that is just me. You go for what is best for you.