As soon as recorder starts, go to the capture area and stand in a T-pose:
After that you can act desired motions. If you make several takes of one actor, we recommend to strike a T-pose in the beginning of each take.
Sometimes it is inconvenient or not possible to stand in T-Pose. You can do without it, but in this case initial alignment of actor model in iPi Mocap Studio
will require more manual actions.
We use tracking data from modern depth sensors for workflow improvements. You can get most of it if you follow recommendations described here