I used to use an exhaust fan about like the one below. It expands to fill the window. If you have open areas in the window, the air will "short circuit" around the fan and not pull any from the room. A fan like this helps a bit but will hardly cure the problem. You realize that, if you push air out of your room, hot air is entering somewhere else in the house to replace it.
https://www.walmart.com/ip/Holmes-HA...YaAvEMEALw_wcB