This article presents Gesture Interaction DEsigner (GIDE), an innovative application for gesture recognition. Instead of recognizing gestures only after they have been entirely completed, as happens in classic gesture recognition systems, GIDE exploits the full potential of gestural interaction by tracking gestures continuously and synchronously, allowing users to both control the target application moment to moment and also receive immediate and synchronous feedback about system recognition states. By this means, they quickly learn how to interact with the system in order to develop better performances. Furthermore, rather than learning the predefined gestures of others, GIDE allows users to design their own gestures, making interaction more natural and also allowing the applications to be tailored by users' specific needs. We describe our system that demonstrates these new qualities—that combine to provide fluid gesture interaction design—through evaluations with a range of performers and artists.