Everyone wants to talk about how many businesses are being onboarded to bitcoin, but no one is really talking about how many customers are actually using it. Business adoption at this point is probably more of a vanity statistic. It's good data and great to get an overview, but what you described is fairly common.

In short, the answer is increasing transactions so staff get practice and feel comfortable. I think it would be far better to have a small number of businesses who know what's going on, with hundreds of consumers using it. Consumers using it would be a natural way to train the staff.

The process for a business to accept bitcoin is insanely easy. If staff can use a calculator they can use a lightning point of sale. My advice would be to focus less on how we can better train businesses, and more on how we can better incentivize consumers to participate in the bitcoin economy more frequently.

Ultimiately the community can help by really making it a point to pay with bitcoin. Perhaps don't be so intimidated by the insecurity or lack of knowledge of the cashier. Become familiar with the tools and know how IBEX, Strike, or OpenNode works, so whenever a flustered employee doesn't know what to do, you can walk them through it and perhaps they'll remember.

Of course, this isn't really scalable, though. The best thing we can do as developers/enthusiasts/builders is to find novel ways to increase the use of bitcoin in some way shape or form so businesses and their staff get more transactions and practice. The more consumers we get to use participate, the more the business will dedicate time to ensure the staff know what to do.

Consumers will be the ones driving demand. I'm learning that more and more!