I was a volunteer when SickKids participated in Science Rendezvous. We a had both to present Sustainable Development Goals and Global Child Heath tools and results to children.
We realized that visitors usually cannot spend a lot of time at exhibition, but some visitors are interested to learn more at free time. So, I created a PDF document with all the important links together which I designed it as a page with clickable pictures.
All the visitors had to do to get the document is just insert their email.
Note: It is not a subscription to anything, the tool just sends the document.