I just use a tag and anything that looks interesting or appealing, I’ll add #[[Vision Board]].
The nice thing about using a Vision Board within Roam Research is that you can link it to another page which can then go into specific details, have more pictures, URL, and so on.
Once I collect some interesting things, I can then filter and then drag the items I want to the Vision Board page.
I use a fairly similar process for writing books using Roam Research.
One of the books is about Charlie Munger. So if I watch a video about him on YouTube, then within my [[Daily Log]], I’ll write with the tag #[[Charlie Munger Book]] so that later on, I can scroll down the references to see what is useful and relevant.