I wear converse all-stars during summertime. Socks are the important thing.

I have two pairs. Next to the foot a sock with 90% merinowool and on top of that a sock with 50% merinowool.

This combo keeps me quite comfortable, sure my feet are warm but not uncomfortably so.

And after a whole day with shoes on the feet are a just a whee bit damp but never, ever soaked.

The 90% sock sucks up the moisture without feeling wet and then evaporates throught upper sock and the canvas top of the shoe.