The easiest way is to store your requirements project into a Project Folder shared on a network drive and use Exclusive Document Edit feature. This approach prevents multiple users to edit a document at the same time to prevent merge conflicts.
You can also store the project files (based on JSON format) in your preferred version control system (VCS). However, merging editing conflicts using approach is error prone so we recommend to use it only to store project baselines and not for true team collaboration.
We are working on the next major update of ReqView (version 3) which will introduce ReqView Team Server allowing seamless real-time team collaboration minimizing resolution of editing conflicts. Later, it will also enable Git like offline collaboration based on commits, branches and tags.