Raul, if you can't find someone to show you, or don't already know the feeling, this may get you started:
Robert John wrote:
Extend the hands outwards on either side. When doing this draw the shoulder blades together while simultaneously dropping the shoulders. This should cause tension to drop from the shoulders, flow to the elbows and out to the fingertips. The elbows and fingertips should feel sore if this tension is held.
Elbows should be STRAIGHT.
(Excerpted from Training the Body. Part 2: Exercises
The first place I could get that kind of feeling was in my fingers, hands, and forearms. Now I can get it across the front of my chest from fingertip to fingertip, sometimes across the back, and keep it there through a range of motion. I'm working on getting that kind of tension all throughout my body all the time while relaxing muscles as much as possible. I figure that once I've got that done my foot is firmly in a door and then the real internal skills work begins.