Before we begin to look at my ideas on improvising using chord shapes, one should have a good general knowledge of the blues (or minor pentatonic) scale and the "Blues Box". If this is not the case, some good lessons to look at before continuing might be: Blues Scales and its Modes, by Fredrick Burton;
Blues Soloing and Basic Harmony, by Chris Sung; and
Blues Scale Construction, by Bruce Maag.
These are a slight few of the many wonderful lessons available here at Wholenote! Good luck and enjoy the power of CHORD SHAPES!