1.Test your website on iPad, and update user agent detection code if necessary.
2.Use W3C standard web technologies instead of plug-ins
3. Check your viewport tag settings
4. Modify code that relies on CSS fixed positioning
5. Prepare for a touch interface
6. Use textareas instead of content editable elements
For more click here http://developer.apple.com/safari/library/technotes/tn2010/tn2262.html