As simple as it sounds, research has shown that proper breathing can reduce stress, pain perception and anxiety. There are many resources your OT can guide your through, but here is a educational link for Diaphragmatic Breathing.
At a recent conference, breathing applications (apps) were also discussed and here are two to try:
1) Breath 2 Relax, developed by the National Center for Telehealth and Technology which provides detailed information on the effects of stress on the body and instructions an practice exercise to help learn diaphragmatic breathing.
2) Simple Being a guided meditation app especially designed for those without prior experience.