Site Design:
Text content should out weight the html content. The pages should validate and be usable in everything from Lynx to leading edge browsers. Avoid heavy use of: flash, java, java script. Go external with scripting languages if you must. Your site should respond almost instantly to a request.

Page Size:
The smaller the better. Keep it under 15k if you can. Remember, 80% of your surfers will be at 56k or even less.

Keyword Density:
Use the keyword once in title, once in description tag, once in a heading, once in the url, once in bold, once in italic, once high on the page, and hit the density between 5 and 20%

Outbound Links:
From every page, link to one or two high ranking sites under that particular keyword. Use your keyword in the link text (this is ultra important for the future).

Links, Cross links, Link backs:
On topic cross linking is very important for sharing your pr value across your site. Find sites that have links pages or freely exchange links. Simply request a swap. When YOU receive requests for links, check the site out before linking back with them.

Logging and Tracking:
Get a quality logger/tracker that can do justice to inbound referrals based on log files

Spiders:
Watch for spiders from SE's. Make sure those that are crawling the full site, can do so easily.

Content:
Lots of text breaks, short sentences, lots of dashes, something that reads quickly. Most web users don't actually read they scan. Use headers, and bold standout text liberally on your pages as separators.