Preparing the Electrode Site
If signals are erratic, one way you can improve electrode connections is to gently rub the area where the electrode is to be placed. This is known as abrading the skin, and removes a thin layer of dead skin from the surface of the skin. Since dead skin doesn’t conduct electricity very well, removing it improves the connection between the electrode and the skin. The skin site can be lightly abraded with a clean dry cloth.
Do not abrade the skin for EDA (GSR) measurement sites.