I'm beginning work on a website whose user base mostly views it in MSIE, specifically versions 7 & 8. Despite this, the website owner wishes to update the website using the latest standards so that it looks better in more standards compliant browsers while still presenting well in these versions of IE.
I'm trying to figure out the best approach to this. At this point, my thoughts are I will be almost developing two separate websites: one that uses the latest HTML5 technologies as much as possible and the other which will rely on a lot of conditional comments and separate styles sheets, images for drop shadows, etc.
My question is: what is the best approach to avoid making a mess while producing the best results? Am I correct in my assumption that I will essentially be developing separate websites for this request?