SEO_WBM is an easy to use on page SEO plugin for WordPress, it is 100% white hat and will automatically adjust its advice as Google (or any other search engine) changes its algorithm.
Currently it's the only free WordPress plugin which actively analysis's high ranking webpages as a basis of its advice and was inspired by my experiences using Internet Business Promoter and SEO Profiler.
Further information and support can be found at (
http://www.websitesbymark.co.uk/seo_wbm/)
Extract the download and upload the folder via FTP or use WordPress install plugins function to install the plugin.
For information on ahow to use please see below.