Onsite Optimisation refers to those activities directly involved with the content and design of the different pages of your website. By having a good onsite optimisation this will help your website be property crawled and indexed by the search engines.
The most important on site optimisation elements:
1) Title tag.
The title tag is the most important meta tag and is still read and indexed by all major search engines.
Limit each one under 65 characters with all your selected targeted keywords in all, using a different title for every page reflecting its content.
2) Description metatag
This tag describes the content of your website. Have it limited under 160 characters and include your main keywords. It should be presented using good grammar and avoiding repetition as it with the title tag will give make the first impression to your site visitors.
3) H2, h2, h3
Include your main keywords in your headings.
4) Add some of your relevant keywords in the content of your pages.
5) Internal linking, Internal linking is from a Seo standpoint very important, you ought to remove any broken links making sure the search engines bots can reach almost all pages in your site.
Helping the search engines navigate the site that can be properly crawled and indexed by the search engines.
6) Anchor text refers to the texts that points to links, here again is a must to include your relevant keywords in them.
7) Image ALT Descriptions, Alt tags carry the same importance for images as links carry for texts. Google uses the alt tags to indexes images inside your site for Google Images. So it is definitely important to have a decent amount of keywords in the description of the alt tags.
8) Body Text, it is important not to forget that your costumers are real people and not search engines, so the secret of success relies in providing them with good and unique content that includes your main keywords.
9) URL, If you haven’t buy your domain yet, make sure to do some research beforehand to see if you can find one that includes your keyword as this will help you with your SEO.
After reading it it looks like there are a lot of staff to do. Thanks for the info.