Summer running equipment - must have

Nothing!
But that would be a bit awkward, so next best thing is as little as possible (Thongs perhaps? No? Still Awkward? Unless you are a girl? or Channing Tatum?! OK, moving on..)  ;)
Then something thin! Very thin!!! But not see through!!!! Think of belly dancers' silky outfit. Also awkward? God dammit...

Then socks. :D I had to start with this. Don't know why. Voices told me. :) Anyhow socks... think of some technical material: dri-fit, climacool or something like that. You will sweat like a pig. In rain forest. In sauna. So... blisters, they're gonna get you. Technical socks help.

Running shoes are also good idea.

Moving up. :)) Shorts, don't have to be too short, 5-7 inches works great for me, not too long, not too short. Also from technical material. I like to avoid tights, cause as much air as possible is most welcome in that region.

Altogether avoid cotton as much as possible as it will get drench in sweat (check part with pig in rain forest in sauna) and then it will become heavy and wet and then starts hell called chafing. And nipples. Blood. THE PAIN!  Nipples are very tender and don't like to be rubbed with wet harsh cotton apparently. Avoid that by any means possible. It won't be fun. Even if you think that kind of stuff are fun, trust me, they won't be. Underlined and bold! NOT FUN!

Bandages and body glide/vaseline are huge help but if you find your self lubed and glued with bandages from neck down wearing thong wrapped with silk scarf you are probably over doing it, so go home and rethink your life..
 
Moving on. T-shirt (technical material, thin, bla, bla...)... Only one thing is crucial regarding tops: it absolutely has to be FLUORESCENT YELLOW color! ;) When you go out and shine brighter than the Sun then you are invincible!!! Take that, Sun and heat!! :D

Aha... Hat, sunglasses, whatever to your forever I shine brighter than the Sun!

For girls:
I don't know. I am not a girl, and only the God knows the ways of the girls so belly dancer outfit with thongs or Princess Leia outfit from Star Wars it is... ;)