With a partner hit each other one at a time using either limbs or the body taking 10 breaths to complete each movement. Use your body and limbs to escort the attack to you without moving away at first and simply feeling the movement and the tension in your partner. This looks weird but it lets you move with your partner without trying to move him and thus to actually feel without fear and tension. Do a few of those from different sides and different limbs. Now pay attention to where your body wants to go as you feel the tension from the attack and let the body move as you still let the limbs simply touch and feel the attack ( you may feel you are already moving him or her without intention because he will feel the lack of resistance and his movement will be grander than his intention) Do this for a while and work on matching his or her speed or less so you avoid flinching by awareness. Start to move as you feel the tension and now while in contact feel where there is an opening and add to the movement still keeping with the 10 breaths per movement and keep the breaths even and relaxed. This is a hard drill especially in the beginning where if feels ridiculous to guide the hits in but consider that when you clean the tension and fear and allow your partner or partners to enter, you will be free to do as you wish as you are within the movement.