My go-tos are: Loose fitting, long sleeved (because of the bugs), light colours (because of the bugs). My preferred fabric is linnen, i find it less clingy and cooler to the touch than cotton, exept for a thin cotton scarf/bandana, which i dip in water (cooling your neck helps cool your body, lots of big vessels close to the skin). Of course a hat. Barefoot, fllip-flops or avarcas
for my feet, if circumstances allow. Avarcas are really nice. Mine are made of bike tires and leather, i had them made to fit for around 15$ and wear them almost every hot day for the last 10+ years. They look much nicer than sandals on my feet (Size 15) and are really light.