How to update HTC Sense ?

Hi, I was wondering if I can update my HTC Sense from 3.0 to the latest version which is 3.5 ?
And in the future HTC release new version of Sense UI, can I update like I update IOS firmware for Iphone ?
Answer #1
Have you gone into setting > system software > update? or something like that
if not go over to XDA, brilliant site