The best way to reduce solar heating through windows is to block it before it hits the glass. Shade Trees and awnings are great for the job but are not always available. Shade trees take years to grow large enough to be effective. Awnings take extra effort to use and maintain. They both are subject to wind damage.
The best answer may be solar screens that block 70 to 90% of the heat from the sun before it hits the glass. Solar screen material is specially made to block most of the suns rays. It blocks most of the solar heating while still allowing ventilation and viewing through the window. Solar screens are just as effective stopping insects as normal screens.
Solar screen material is more expensive than regular screen material so you should use it just where you need it. South and West facing windows will benefit the most from solar screens. Screen doors on the South or West side of your house will help block solar heating if they are made with solar screen material.
On the down side, solar screens will make the inside of the house a little darker. Dimming the lights always makes me feel cooler anyway.
Solar screens should be removed before the heating season to allow beneficial solar heat to hit the window glass.