We are going in July as well, and are just preparing ourselves for crowds so as not to be surprised by it. In a weird way, we are actually looking forward to it as the crowds and heat will force us to take a more relaxed touring style, including breaks and naps at the hotel, instead of the 12 hours of themepark commando-ing we tend to do. Like others have said, just expect the worst of crowds and heat, and be prepared for rain. It looks like you will be there long enough to slow down a little and have time to see everything.