There are so many factors that can affect your ranking. The some Do's and Dont's are there while doing on page optimization

Some quality on page optimization techniques are-

1. Keyword in URL
2. Keyword in Domain name
3. Keyword in Title tag
4. Keyword in Description meta tag
5. Keyword in Keyword metatag
6. Keyword density in body text
7. Keyword in H1, H2 and H3
8. Keyword font size
9. Keyword phrase order
10. Keyword in alt text
11. Keyword in links to site pages