What you should pay attention at!
Have your client in mind!
The design must not become more important then the content of your pages. Don’t figure the user knows what you have to offer.
Make it simple, make it clean!
Get rid of everything you know your client will not use! Even though you might like it.
Make sure it's in the right place!
Remember that it might not be so obvious for your client what to do. So put everything in the right place