File upload directory structure

hello, I am building an application where different users will be
uploading multiple documents and I would like some advice about how to
save the document into the file system.

What i know so far: I have a document model and it has some attributes
about what type of document it is, when it was uploaded, the url (or
filename) of the document, and more.

I guess my questions are:
Would you save all of the documents into one directory?
What is the naming convention you would use?

Any suggestions or examples of what you’ve done in the past would be
extreemly helpful to me,

Thank you for your help,

Nate