Built in fans in the Kitchen and bathrooms, and portable fans in windows, can cool off your house faster when the temperature outside drops in the evening, but don't leave the windows open when you are out.

If you have a limited number of fans try to position them in pairs, with one blowing cool air in and another blowing air out after travelling through the house. Consider which side of your house is shaded in the afternoon as the best cool air source, but if there is a strong breeze or wind you may be better off working with the natural flow of air than trying to work against it.

Open doors along the travel path of the air.

http://www.wikihow.com/Use-Window-Fans-for-Home-Cooling

https://www.overstock.com/guides/tips-on-cooling-your-home-with-window-fans

If you only have one fan you may want to focus the cooling on a bedroom, leave the window there open and put the fan away from it.

http://www.instructables.com/id/Cool-Your-House-With-Negative-Pressure-Ventilation/