Those are some useful tips for web designers , hope that it will help you :
10 - Try to avoid using flash and rich-media content to present your information. Search Engines cannot read through video clips, pictures or flash banners.

9 - The website belongs to your client, so take the time and visualize what he wants rather than what you want to give him. Your job is to turn his dream into a reality, not make him accept your dream!

8 - Cross-browser compatiblity is a must. If you’re serious about your craft, you need to take the time to test your creations in different browsers. Just because you’re using Firefox, it doesn’t mean everyone is. Also, always validate your code! http://validator.w3.org is a very good start.

7 - Most people read from left to right. Put your important information to the left of the site. (more…)