You can create a local model from the central by simply opening the central model and utilizing the CREATE NEW LOCAL toggle (turned on automatically whenever a valid central model is selected). The central model will be copied to the user's DEFAULT PATH FOR USER FILES setting. This is faster than copying the central model from the network to your local drive, renaming, opening and clicking through the "this model has been moved from X to Y" message box. It also ensures that you're always using the latest and greatest version of the model. If you haven't worked on the local model for a few weeks while others have, when you open your local file you may not be able to reload all of the latest changes because there just may be too many. Personally, I like to copy/rename/open the central model because I like to keep my local models organized in a similar structure to our network (I.E. project number and name).
So to answer your question, either way of creating a local file is acceptable - one is just faster than the other.