Take a leaf from the californians books.......ac and tinted windows in the cars and ac and ceiling fans inside.
Oh and I hated wearing a poncy fookin suit in the UK and for what? Did I meet any customers? No. Stupid crappy tradition that should go the same way as the 1800's practice of wearing a hat. Smart informal dress if you please and it'll keep me cooler as well. My wee rant over.