Optimizing websites for Google is becoming harder and harder. It’s now not just a case of adding keywords into your various HTML tags, uploading your files and waiting for the results.

This type of optimization, commonly referred to as on-page optimization, will only ever be 20% effective at achieving rankings for keywords that are even mildly competitive. Those of us who aced maths in school will know this leaves us with 80% unaccounted for.
This 80% corresponds to off-page optimization. Off-page optimization is all to do with:
The amount of links pointing to your site and its pages
The actual linking text (anchor text) of these links
The quality of the pages which the links are on
On page optimization
On page optimization is what can be done on a website page to maximize its performance in term of ranking highly for target keywords used by a target audience and producing sufficient referrals and conversions:
1.Create effective Page Title to generate high-ranking effectiveness:
Combine keywords and relevant call to action in a readable fashion to drive ranking and click through rate. For example: Quality Power tools - Buy now and save - Brand Name(if not used in the domain name)
2.Influence your Snippet and Page Description: Snippet is excerpt from your page. It is shown under your page title in the search results page. Ensure first occurances of your major keywords come together that the snippet is a factual and relevant representation of your page
3.Make your body content relevant to the overall page topic/theme and target keywords: If I am optimising a Power Tools page I am expecting to drive the searchers searching for power tools to that page. So my important sections on that page such as headings, emphasized text, paragraphs, etc will need to have power tools keywords naturally used in the content.
4.Links: Make it easier for the end user and search engine to understand the flow of your website content.
A word of advice, write naturally for the end user not the search engine. Doing so will positively influence your relevance factor and ultimately improve your website ranking and conversion rate. Ask yourself what do your visitors need to know? And how can you help them get what they want?
Off page optimization
Off-page optimization is what can be done outside your website to positively influence the search engines ranking and page popularity for target keywords related to the on-page content and keywords in off-page direct-links
Search engines value links and attribute the highest page ranking factors to pages with many links from high-quality sites. In general, webmasters can improve the rank of their sites by increasing the number of high-quality sites that link to their pages. It is not about quantity but quality of the websites linking to your website.