A hot streak occurs when you get three stars on two moves in a row then any additional three star moves is considered a hot streak. The hot streak stars have a blue trail. Keep this up for six moves or more and you’ll unlock this achievement.
I found that by dancing to The Fresh Beat Band song ‘Get Up and Go Go’ in ‘Starting Steps’ and using my chair in front of the Kinect (instead of actually dancing), I got a nine-move hot streak without even trying. I also got three Gold Stars without doing anything. Results may differ, though.