I think you have to formalize the process first. If everyone in the company does something different every time a requirements doc is written, it is just chaos. Steli and Hiten had a great podcast episode on this recently.
As part of that process, you will need tools to capture the documents and track changes to them. Consider something like Confluence or another type of wiki. You will also need good training. If you expect people across the company to use the process, you have to make it accessible and easy for them to learn.
A book I would recommend that I am working through now is Writing Great Specifications by Bicieja
