I was a snowboard instructor for two years out east. Private lessons is not a bad idea but can cost more then a group lesson. If your already linking turns you should be fine. It all about how confident you feel in your riding ability. Try a technigue called the falling leaf where you stay on your heal side going right then left keep your head up and focus of where your going. Then try the same method on your toe side. I have found when I showed my class this that it helps for linking turns better.
watch vid you tube or what ever. I used to watch a snowboard class when I was learning and started to figure it out from there.