It's easy to create a custom node with CCK, but what if we want to change how the node looks by default? It's a step up from theming your submitted and your terms code, but it's not really that hard. The main difference between theming the CCK node and the regular node is that in node.tpl.php, we have several content sections within a node, so rather than just printing $content, we will print out parts of the content individually. I will use code from the wallpaper node type of this site for my examples.
Step 0, before we get to the phptemplate part of this tutorial, you have to think to yourself if you really need to theme a specific node programmatically. In many cases, you can style a node just fine with CSS only, so first imagine how you want to theme your node and determine if you really need to get into the templating engine.