Great post, Graf1771!
Adding my suggestion, which is kind of a continuation of Janeth's 5-second rule --
Watch out for the size of your graphic images. Just because they
look small, it doesn't mean they are.
I've seen lots of people who think that they can resize their images by simple setting the image size to 50x50, when the original image is actually 600x600 and 90k! That's just not how it works.
Resizing your image means shrinking the
actual size of the overall image. This means changing the actual dimensions (height and width) and the dpi (dots per inch) and the "weight" of download size of the image (file size in "k").
There are plenty of programs out there that can help with this. For example,
GifBot is a free online tool that can help resize larger images into smaller ones.
Too many large images will drive your visitors away (and too long a download time) faster than you can possibly imagine! That's one of the first things that every beginner should be careful of when designing websites.
Just my 2-cents.
S