In the past I have talked about why clean web design is best but yesterday it occurred to me that some people might not know what "clean design" really means. So here are some things that characterize clean web design. If you want to make your website better, I recommend you make your design follow these!

Let's start with some of the bigger (more obvious?) ones and work our way down.

1. No animations! The number one thing you can do to make your website look junky is to have animations on it. Animated GIF images to those "cool" flash things are just plain un-clean design. They distract your users which don't give a darn about fancy (and in some opinions ugly) fluff. Would you use google if they had a bunch of flashing ipods that you could shoot at? I would go use Clusty!

2. No Popups. OK, I think just about everyone knows not to have these, but just making sure.
3. No intro. Don't have an intro to your website. The only people that like them are people that make them. And most your visitors won't make them (and thus won't like them).
4. Abstain from using flash as a UI (user interface) widget (such as a button or something you would use to navigate your website.) Flash is good for youtube movies, google analytics, or browser based games, but not for your design! If you disagree with me go ask someone who heavily uses flash for design to get an answer that will make you happy - but you won't get around search engines not being able index your site properly (google can't see links nor content embedded in flash.)
5. Good color scheme. It is necessary to have an appealing color scheme that doesn't blind people or make them cringe. A good place to pick a nice one up is Adobe's Kuler.

6. Few images. Try to make your site use as few images as you can. They increase load times (as well as the amount of bandwidth you have to pay for) and are difficult to make look good. If you are good at making images look nice in a design, be sure to keep their size down as much as you can while still retaining high quality (use the png format). I'm not against using images in a design (I use them in this tutorial), just be careful!

7. And last but not least, make sure your homepage is good! Best way to scare off visitors is to have a bad one... and the last survey I saw showed that most web masters want their visitors to stay.

And that's all folks! Well, not really, but a good start. There are many many more small things you can do to make your design cleaner, but these are the main ones.