I don't think it is as complicated .... I have offered refreshments, the tickets are available on the weekend in a tent on the village green, our village is small so everything within walking distance, have to stipulate whether suitable for the disabled ( unfortunatley I have steps)
Think I was thinking more about break ins, etc, or stuff being stolen after the event.
I only have a very humble garden, no specimens etc.
Our village has open garden day every year, and it gets very busy. There is not really any descriptions of features etc, just a little map showing where each garden is. Like you our garden is quite small, but very busy, and we have steps everywhere, so we wrote a big chalk board, at the gate reading 'welcome to our garden, although its very small and humble, but please watch out for all the steps, we'd hate to see you tumble.' Keep your curtains and blinds pulled. Entrance fee was paid at the villahe hall, and we each knew who had paid because of the map.
We all stand around in our gardens, be cause people wil ask you questions etc, and want to share experiences.
It all finishes (if people want to) back at the village hall for homemade cakes and tea.
We love it its great fun and the visitors are always so nice. Hope you do it, good luck, Mrs Bouquet