There are multiple ways to share a document with some who is not subscribed to Final Draft Cloud.
Similar to the desktop version of Final Draft, you can export your document as a PDF and email it to them via your email client of choice. Here's how to export a PDF from Final Draft Cloud: How do I save my file as a PDF in Final Draft Cloud?
You can also share your document via using your address book and the Sharing function in Vault. See these steps for how to do so:
How do I share my script with another Final Draft Cloud user so we can write together?
When sharing a script with a non-subscriber, they will only be able to have "Reviewer" permissions, meaning they can read your file and add ScriptNotes, but not make any edits or changes.
For more information on using ScriptNotes, click here:
Inserting and Managing ScriptNotes in Final Draft Writer