@bmike has some rather well thought out questions and more than a few answers to issues surrounding helping folks with their intent to install or actual installation of the public beta (and presumably the dev install) on a Mac they have access to.
I was brought to this thread by his link in a comment on a comment I had made on a question that felt like it had gone off the rails.
No doubt others are familiar with the well intentioned answer that goes into a great detail on if this should be done or not. Which is certainly a question that should be answered, but in this particular case didn't really answer the question:
Would creating a bootable installer and booting from it be a good idea, when I'm working with a Beta version?
If you work in IT support (as I do) you learn to understand (or at least interpret) a user's question "why can't I print to PDF?" (for example) as "I don't have a PDF printer option any more, how do I get it back?" EG a non-technical question about a technical subject.
I interpreted that particular question as the question's author assuming that the beta installer was somehow special/different from the installer you would get from Apple to upgrade from Sierra to High Sierra. Which it might be.
So I ask the obvious (to me...) question
[...] have you tried making a bootable installer like you do any other macOS installer? Instructions here from Apple support.apple.com/en-us/ht201372
Pointing to Apple's article on how to make a bootable USB installer for macOS.
bmike suggests that this should be an answer. Valid point.
But I have not actually tried that method with the public beta and am loathe to provide an Answer when it is little more than a suggestion that may or may not work. It seemed too brief and off the cuff to be an answer but it did seem worthwhile, especially in light of the other answers that were less about actually installing the software and more about if you should.
I will often make such suggestions in the comments if a possibility springs to mind, especially if I haven't tried it myself, and wondering if that would be an acceptable use of a comment?