Some guidelines:

1. Make a Great First Impression

Is this site credible?
Is it trustworthy?
Does it look professional?
How can I find what I want or need?
Does this site make me feel welcome?
Am I in the right place?
2. Maintain Consistency
3. Use the Right Images
4. Create a Solid Navigation System
5. Limit Flash and Animation
6. Make it Accessible: Make sure that anyone visiting your website can view it no matter what browser or application they’re using. In order to gain significant traffic, your site needs to be compatible with multiple browsers and devices.

So please give all this question answer in the comment section