I scattered it by hand in August. I think I may have used a metal rake to try and score the dirt a bit so it could take hold. I watered for a couple weeks then stopped.
One dog. She likes to run through this particular patch. Along the specific path she runs it took a bit longer to grow but then has held up well.
I've added clover into some of my lawn. It took an area that was dry, dusty, and worn and has made it lush and green with no other changes to lawncare. The grass in areas with clover added is looking better too.
I used a micro clover I got off Amazon. It took until the next year for the clover to really get going. The first year it was a bit thin.
If the form allows, perhaps a "not listed" option that would then show a follow-up question with a text box where people could suggest additional entries.
You wouldn't have to aggregate all the custom entries if it was too onerous, but if you spotted a pattern/some frequently entered things you could then include them next time.