The most important tip for anyone wanting to get high search engine rankings for their website is that the critical time is before you start setting up your site:
* You must undertake through keyword research. It is important to find keywords which have a reasonable search volume but not too much competition. Pages and posts can then be built around these keywords. If you pick highly competitive keywords, dominated by established sites with lots of backlinks, then achieving a high ranking may be impossible unless you have lots of time and money.
* Your domain name is an important factor in SEO and you should aim to get a name with the primary keyword near the beginning.
Once your WordPress site is live you should address the following before thinking about WordPress SEO Plugins:
* You need a theme designed for SEO as well as for appearance.
* You should configure the Permalinks to "Postname" so that the page/post title appears in the URL.
At this point it is appropriate to think about WordPress SEO Plugins:
* A good starting point is to install a general SEO Plugin like "All In One SEO Pack". This has a number of useful functions, which you can adjust, but it is quite satisfactory to start with the default configuration. To complete the installation all you have to do is compete the meta data for the home page.
* Of the other WordPress SEO Plugins there is one other type that you should install immediately. This is one to create a sitemap for the search engines. This will help the search engines find all your content and speed up indexing.
There are numerous other WordPress SEO Plugins that you could install all of which help some aspect of SEO. However, if the points covered above have been addressed the most important thing is now content. Content must be unique, be build around a keyword and be written in a search engine friendly manner. This means that it should be written primarily for visitors but in a way that the search engines can understand its relevancy. What you must not do is write it primarily for the search engines as this will be seen as an attempt to manipulate them and will be punished.
One of my favourite WordPress SEO Plugins helps with this. It is called "SEOPressor" and when you create or update a page or post it checks the on page SEO and gives it a score. This includes things like checking that they keyword has been used in the correct places at an acceptable density, that you have internal links and external links and that external links are nofollow. You simply follow the plugin's recommendations to maximise the score.