Everything DEPENDS Is your room window facing the south? Do you have solid curtains(or lined)?...close them...keep it shady in your room. Windows are closed tight during the day. Think of heat like ice cold winter. Hot or cold...we want a temperature that is at neither extreme. Is the window double pane(or is it just a single sheet of glass) Singles let in the heat and cold so fast. Having curtains drawn closed will slow down that process of temperature change.

. is your room insulated. Insulation slows the progress of heat as it does against cold.(if you live upstairs near the ceiling then your room is going to be hot, especially if you have dark shingles.

..>simple experiment. Go out into a parking space in the full sun and put your palm against a car that is dark colored and feel the temperature. Now go to a white car and feel the temperature. Generally there is a noticeable difference of which is hotter. House is no different. If your walls are not insulated, then it is not worth the cost to rip off the drywall and fill the hollows with insulation. And then put back up the drywall. and refinish and repaint.

. The easiest thing for you to do is move into the cellar or basement which is the coolest part of the house.Summer and winter. Other than keeping the window closed and shaded during the daytime...

...open the window fully during the night. Now you need fly screening on the windows to keep the mosquitoes out or you will have donated a pint by morning, I put a cold air box fan in the window exactly the size of the opening or I cut cardboard as a filler to close the space around the fan in the window so it has to take the inside air out and blow out the hot air. I also open a second window across the house which is on the main floor on the North side to allow in the cooler air.(as I got to cool down an entire house) This runs all night long. In the morning I shut off the fan...close the windows upstairs and down and lock in the cool air inside the house for as long as possible. Which is about 3 PM. Then I find other activities to do before I can start the "air flush again"

Doing just a single room...all you can do is run a circular desk fan at low speed continuously. As you sweat, the fan air blows past you and the sweat evaporates, cooling you off. Yeah sounds grody, but have a hot shower in the morning and you are cool for a short time. Sit under the shade of a tree. Tree shade is cooler than building shade.

Put a table in front of a window that is partially open--with as much glass as possible shaded from the sun, place a fan on the table drawing air into the room, and place a big bowl of ICE in front of the fan so it blows across the ice into the room;and, if you have a second window opposite that, place another fan on another table pulling air OUT of the room and exhausting it to the outside.

Install a ceiling fan.