My PSR really begins with the walkthrough, since everything is based on what I figure out during that few minutes. When pasting targets before I'm up, I usually zone out to an extent and just clear my mind. When I'm on deck, I run through my stage plan a few more times in my head. When the targets are being scored and pasted for the last shooter before me, I take a final walkthrough. During the make ready, I manipulate the gun in the "face box" only. After the make ready, I take a few deep breaths and position my off-hand where it needs to be for the start while keeping my right hand either on my gun or on my stomach (not in the start position) until I am ready. I move my right hand into the start position when I am good to go. I inhale one last time at the "Are you ready?" and exhale at the "Standby".
Pretty simple eh?