My first trip, I asked the DW to get out and watch out, she walked behind the TT. I stopped, got out, and walked behind the TT and just stared at her. Her response was "What? I was giving you the thumbs up!".
When I came back down to earth, I explained that we have to be able to see each other in the mirrors to communicate.
It took a few trips working my best to avoid using a spotter that was on my skill level. I got a lot better fast and so did our trips together.
She now says she worries about me traveling and parking without her.
My blood pressure is constant now. Just took practice.