Basic On Page Ranking factors

1. Title Tag - Description of Website
2. Domain Name
3. H1 tag or first headline of document content
4. Description Meta Tag
5. Keyword Meta Tag
6. Body of Text Italic
7. Body Of Text Bolded
8. Body of text generic
9. Keyword Density 5-20%
10. Latent Symantec Indexing - Related words on topic
11. Sub headlines H2, H3 etc
12. Phrase order within the page
13. Keyword proximity of eachother
14. Font size +2 for sub-topics
15. Keywords within your alt text of image descriptions
16. Keyword early within the page
17. Keyword in links to other pages (on or off site)
18. Quality of other sites you link to
19. Topic of other sites you link to
20. Tree like structure of navigation
21. Internal links valid?
22. Number of links on the page itself (less is better)
23. Domain names you link to (Gov is best, then .edu, .org etc..)
24. Web page size (IE: under 100k)
25. Hyphens in domain or file names more than 4 is bad
26. Page changing, more often updated pages prefered
27. Domain age
28. Page itself Age
29. Sites with more internal pages (IE: over 100 internal pages)
30. Page Theme
31. Frequency of updates themselves
32. Interesting title tag - Gets more SERP clicks than another
33. Appropriate links between itself and other pages
34. a robots.txt
35. a physical address (Trust)
36. Stating a support email address
37. Describing every image
38. Naming the images themselves thematically
39. Keyword in name of page itself
40. Document within a related folder or subdomain