How can I deal with the heat??!!!?

I'm in the UK, which is generally quite cold and suits me absolutely fine because I really don't like the heat AT ALL. But for the past week it's been very hot and sunny and I'm finding it really difficult - I hate being hot, it makes me feel physically ill, and I hate being sweaty all the time, it makes me feel really dirty. I can't really go out in the sun because I burn ridiculously easily, so I'm spending most of my time indoors, with a fan on and all the windows open, but I'm still finding it unbearably warm. Short of having cold showers throughout the day (and night!) what else can I do to make it easier?