The Logo
I mention this outside the "web page setup" on purpose.
If you make your own web design, you usually don't take the time to
really think about a logo. If you have somebody else do the page,
he/she might overlook it as well, or the web-designer would expect
you to supply the logo.
Lucky you, if you are a graphic designer and/or you have a logo already.
In case you don't: Invest some time and a few $ to get a good one:
It is the image that your visitors will associate your site with.
If it looks crappy, unprofessional or cheap: this is what your web
site will emit.
Refrain from using rotating or animated logos. It is no more than
a gimmick and it is getting old very fast. In the worst case it can
just annoy your visitors, and they leave before you want them to.
Always remember: Visitors come to your page for the information you
offer or for the items you sell. They are not there to marvel at your
web design or logo.