It gets hot here in Gods' Country. Wriggle your arms to get as much airflow under your jacket as possible. If necessary, flap them now and again.
People fall over a lot.
Ones that stay upright have a clammy, bleached worm look about them. Carry a bottle of water with you. Whenever you stop, wet down your t-shirt under your jacket. Do not worry if the water you use is hot. Once you set off, it won't make any difference Visit garages with hoses.