Title
Description
Headline
Good Keywords
Alt Tags
Great Content(very important to search engines)
1) Keywords
Your keywords are SOOOO important. It's how Google finds your page in the first place. Your keywords, title, and description is whats going to tell Google whether or not to recommend your page the person searching. http://www.website-help-from-ebooks.com/good_keywords.html
It's recommended that your keyword should make up of 2% of your content. It's a delicate balance. Too much and the spiders might look at it like spam. Too little and it might have trouble determining what your page is about.
Your keyword(s) should be included in the description, title, and the headline.
You can search for the correct supply/demand keywords on various websites - http://www.wordtracker.com
http://www.adwords.google.com/select/Key…
These websites will help you decide keyword profitably, supply/demand, CPC (cost-per-click) and much more.
2) Content
The SEs LOVE fresh, new, juicy content. By updating content on a regular basis you're telling the spiders that you're helping your visitors by offering them frequent information. That makes the SEs look good, and makes your visitor want to return. http://www.website-help-from-ebooks.com/website_content_ebooks.html
Great content is a big reason why websites and blogs become so viral. By having a unique voice, your visitors are going to trust you and the valuable information that you're offering.
Hope this has helped, good luck.