I purchased a house where my master room will get baked by the sun every day..
my wife is gonna have her confinement there for at least a month..
She would want me to get the sun fix so the place will be cooler.
Our neighbor had installed a balcony and installed those blinds to block the sun from entering the room..
i think that will be rather costly?...
The most effective way is to block out the sun from hitting the windows.
Those sun-shield films will offer little relief if your windows are getting the sun the whole afternoon and don't forget you need to close the windows the whole day to let the shield work.
If you are considering to install those roll-up bamboo blinds as suggested, fix them OUTSIDE of the windows to block off the sun's rays and preferable provide a space between the blinds and windows.
Alternatively, consider installing sun breakers or awnings over the windows I suggested earlier for effective sun blocking and you can open all your windows for natural ventilation during your wife's confinement.