Right procedure when you develop a WP Website for a client

This is a suitable method. There are plenty plugins in the WP Plugin Directory that can ‘migrate’ your site for you including plugins and their settings. All you then have to do is create a database on your clients site (and possibly directory if required) and then import your clients site/files/data.

Another thing you can do if the client site your working on is going on a new domain name / directory that they have never used before you can develop the site live on that domain if you must but I would recommend password protecting the directory until its ready to be viewed publicly.