Lots of treats and praise is a technique I'm employing with Nelly and it's working very well

She used to tense up, back up and spin round so she could see me but since I've been treating her for standing still and moving away from me she's far keener to comply and as a result, more relaxed. We're still mostly long reining on circles to make it less stressful for her as she can see me for most of the session but when I do ask her to turn away, either for a change of rein or for me to walk behind her a while, she's not so worried about it anymore.