if you have one and only one opening into your room, id believe setting the fan to exhale is optimal, as the logic would be similar to radial fans in low airflow situations, where in that situation, its ideal to move hot air out.

if you have 2 windows, I think it was one intake. if you have a window and a door (to the rest if the house), placement depends if youre okay with dunping heat into the other part of the house or not.

theres a lot of factors though, as it pertains to the rooms internal pressure and the condition of the air/sunlight outside of the window, as well as how high the window is