Try and get your html as small as possible, by stripping spaces, and unnecessary tags / comments. There are some great CSS Compression tools around that will shrink the size of your css, and make your javascript files as minimal as possible.

If possible, use gzip compression when sending your pages – oh and you can gzip javascript and css files as well, which makes filesizes even smaller again.

Also, to reduce load on the server, where possible cache (on the server) anything that you are creating dynamically. Your server will only have to spend CPU building the page once, then it just sends the cached static html.

Look at the cache (browser side) headers you are sending, and send instructions to the web browser to cache the web page / css / javascript.

If you are using a database, do your best to index, optimise and normalise your database / queries. Poorly designed databases and queries can really slow page creation down as a database grows. Also, if possible, cache your queries.

Find the best balance between filesize and quality for images. I go one step further and try to work out the best combination of sliced images for smallest file size. Play with gif / jpg / png image types to see how small you can get a file for the best quality.

Well that’s all I can think of for now.