Step 1: Code
To the natural designer, paying attention to code will be difficult at first but will prove invaluable to understanding the technology behind the art. As Jeffery Veen says, "Good design is much more than decoration, it's well-written code."
Step 2: Versatility
One of the first things I learned when I started building websites was that not all browsers will view your page the same. This is such an important consideration for aspiring web designers. You should take into consideration that if you add a video or some flash-media to your site, not everyone may be able to view it.
Step 3: KISS
Most print designers know about KISS (keep it simple stupid.) The same applies to web design. An overly busy website will make your viewers run for cover.
Step 4: Use Pictures
Once a viewer lands on your site you have 10 seconds to grab their attention. Pictures are faster than words.