1/ Lots of content, preferably grammatically correct
2/ Get a listing in the ODP
3/ Get a listing in the Yahoo Directory
4/ Make sure titles are your keywords in a natural non-spammy form
5/ Build new quality pages with lots of content on a regular basis
6/ Get quality incoming links, avoid dodgy link exchanges with dodgy sites
7/ Check a site carefully before you link to them
8/ Avoid duplicate content at all costs
9/ Make sure internal navigation will move people and bots around the site... don't have any orphan pages
10/ Use validated html code.
11/ Avoid flash, (a personal view... I hate it)
12/ Forget about appearing well in the serps if your site is about something that's extremely competitive.
I'm sure there's lots more I missed
