[JohnfAclambrJA]

At one point in life I did some pretty intense sports like triathlons and marathons so keeping cool was very important to me then and a lot of what I did then I still do now before I play on a hot day.

I wear lots of light coloured, loose fitting clothing, lightweight shoes that breath and breathable socks. If I wear a hat it has to be one that is lightweigh and very breathable, prefer mesh. Most of your heat is lost through your head and torso, the two areas you cover up.
Drink: I drink a litre of water just before going to bed on the night before playing and I'll drink some more before going out to play. Once I'm out there playing it's water and electrolytes. I'll sip water most of the day often taking a swig between shots as I'm walking to my ball. The key to fluid is start your round well hydrated and just keep yourself topped up with small sips throughout the day. I'll probably drink 2 litres while I'm playing if I walk on a really hot day.
Food: try not to eat anything really sugary on the day you play, your body will burn this quickly and create extra heat. Key is carbs the night before like pasta or rice.

And sunglasses. Whats cooler than a pair or RayBans really?