Elliot Back has written a really cool Wordpress Customiation for Newbies guide that helps you convert a new Wordpress installation into a customized blog in just a few steps. You should definately read his full article, but in a nutshell he suggests you start with the following tips (& he goes into far more detail on exactly how to implement them)

1. Get Kubrick, a drop in template for Wordpress, and install it
2. Import your links. The fastest way to do this is to use OPML from your favorite RSS reader. It will have an “export to OPML” option somewhere, which you can use to save all the feed URLs to a file that you will import via WordPress->Links->Import Blogroll
3. Get some plugins, and modify them to suite your tastes. Asymptomatic, the WordPress Wiki, Kitty’s Plugins, and the Web Log Tools Collection are all good places to start. Elliot’s top 5 (quoted from his post):

   1. Insert a breadcrumb navigation on your page
   2. Add an Acronym Replacer so when your write AOL, it looks uber-stylish
   3. Turn on the built-in WordPress->Plugins->Search Hilite
   4. Get an automatic linkifier to create links for you, when you only have the URLs.
   5. Random file is another useful WordPress plugin. I use it to rotate the banner of my Kubrick by adding a folder for random images.
4. Turn on pretty links. Actually, I wrote an entire post on how to create search engine friendly permalinks that I think explains it a little better, so I’d recommend giving my post a read on this topic.
5. Ping some services. If you ping popular blog notification services, you’ll start getting traffic to your blog nearly immediately!

Great post - thanks Elliot!