Here's a brief one I use. I'd love to hear how you people do it. Not perhaps in order, but a useful list for some hopefully.
1. Build template using semantic mark-up with CSS/XHTML
2. Validate with W3C for valid code
3. Verify on major browsers
4. Remove style sheets and view if it makes sense
5. Get people involved and note their process/difficulties around the site
6. Use CynthiaSays
7. Broken links?
8. Use correct DOCTYPE?
9. Well-structured mark-up
I guess this could cover Usability to a certain extent, so please contribute if you have further suggestions :)
I'd go a step further and add the following for a more semantic approach:
- Add title & alt tags for everything possible (and make sure it's descriptive, not just alt="Picture")
- Construct data tables properly with thead/tfoot/tbody, th and caption elements.
- Use DL/DT lists for forms instead of tables/divs
- Use label elements for all form items.
- Add #top, #bottom, #menu and #content anchors, with links to then place appropriately around the page if the distance between them is large.
- Don't break content down into small chunks across multiple pages. It's a nightmare in a text-only browser, with a screen reader or with large fonts.
- Test your pages with magnification turned on and make sure the layout scales gracefully as font-size increases.
I also like to check the following on all my sites
1.Grey scale contrast - this is really useful if you are using monotone colours.
2.Check what the colours are like for colourblind users.
3. Run it through Lynx or even better find some one who uses a braille reader, a friend of mine is blind and I get him to work my sites over, his input is often invaluable.
4. If you have any friends who are dyslexic get them to read through the site , as see if they have issues with screen layout and or problems with the font used.
Great stuff, I had something to add but it seems to have slipped my mind.
Also - make sure you can navigate the site without a mouse.