Take for instance on Monday when I was leaving school and Andrew walked up to us wearing his headphones around his neck. They were the old school noise canceling headphones and they looked like giant black eyeballs growing out of his chest (see photo below).
HRH freaked out! She started barking, the hair rose on her spine. I did a correction and still she barked. I put her in a down stay and stopped Andrew. Fortunately for me, Andrew is a really nice kid and was perfectly willing to stand still while a clearly suspicious HRH stared at him from a down stay.
"I know it's not you, Andrew." I said, looking at him trying to figure it out. I let her out of the down stay so she could come closer. She jumped up and went for the headphones. Ah ha!
I put her back in a down stay and had Andrew take off the headphones. I gave the headphones to her. She gave them a bite. Then a lick. I gave them back undamaged but slobbery to Andrew. "Thanks, man! She thought you had weird giant eyeballs."
During a talk with our neighbor and fellow puppy raiser Stephanie, she said she had some old school headphones she could bring us so we could practice desensitizing HRH with them. So Fred wore the headphones and she reacted to them. We realized that we didn't have the training collar and leash on her and had to stop and get that on her to continue. Once that was done, we were able to control her better and hold her attention. Then we switched so I had the headphones on. No reaction at all! Success.
We tried it again this morning with Jan helping us and she ran over to Jan and acted like she was going to bark, but sat at her feet and wagged her tail instead.