There are some basic steps you can follow...
1. Minimize the number of HTTP requests in pages.
Eliminate all unnecessary items from your page. Try to club small css files in a single one. Use less images in your page. More HTTP requests will in crease your page speed.
2. Optimize Images.
Normally images are the heaviest files in a page. Try to optimize the images as much as possible. Use better image editingsoftwares and make them as small as possible in weight.
3. Minify Scripts.
Try to minify scripts like JS, CSS, HTML. Jquery has minified versions of all of their versions. Also minify the CSS files. This will increase your page speed pretty good.
4. Compress contents
Use server features for GUNZIP the pages. This will compress the pages and deliver it to the user browser much faster. Apache has default plugins for this.
5. Defer Page Loading
Try to use ajax or similar technologies to deffer the page load. Load different parts of the page separately through ajax. This will give a much smoother experience to the user.
6. Use external paths for JS and CSS files.
Try to use external servers to keep JS and CSS files. This will give parallel download of files. Most of the leading JS libraries gives popular CDN servers for JS files.
7. Use CDN.
If your site is image heavy, try using CDN technology. This will serve the media files from the nearest servers of the requested ip. So the page load time will be much faster.
Try to load the JS files at the end of file. As the JS blocks everything below this, while executing or loading. Heavy or complex JSfiles at the top of the page may slow down the pages heavily.
9. Optimize your code.
Write code in efficient manners. Try to wave out all un necessary codes or CSS classes. Better and managed codes can save u hundreds of lines, because every byte matters.
10. Dont resize images using HTML.
Always re-size the images properly before rendering in the pages. The smaller the pages, the less will be the download time. Resizing with HTML actually download the bigger image and then shows it small.
11. Avoide 404
404 in a page can slow down the page and the server drastically. Use debugging tools to find out 404 links and correct then.
Hope the above points help you to make your web pages much faster... Suggest me some more as well. Because there are several methods, i have not mentioned here...