To those talking about dark coaches, please keep in mind that the roofs are always white no matter what color the coach is. Granted, the sides heat up as well, but the roof is the big factor.
Now to the original question. Here's what I did on my old coach. I added a second AC in the master bedroom, I tinted all the windows except the windshield, I added the foam paddings to all the fantastic fan vents and I attached some reflectix to the shower skylight (I used snap clips in the installation to easily remove it while showering). I always put out the awning, looked for shady spots to park and tried to park the windshield away from the sun.
Had I owned the coach longer, I would consider the outside windshield covers. If things really get out of hand, you could always go outside and spray down your coach with water to cool it down. Of course most of these suggestions apply only if you are stationary.
I once had to put up the dividing curtain behind my drivers seat when the roof AC gave up the ghost.
