How to keep the sun out of a our sunroom when its hot?

I put up regular 2 inch blinds, I can turn them to be upward to let in air and not the direct hot sun. Or you could choose shutters.

I have used foil, tapped to styrofoam, and this is fine. If you choose to only use the top part, this will help too. If you have like 3 windows, you can close off the 2 on the outside, and still have one that will let the lite in, or cover them all, for shade. Also, use lined drapes on your window. J.

Get th film that will block the sunlight but you can still see through it. I used a bamboo shade that was long enough to cover my dining room windows all at once because of the east windows that heated it up so bad in the morning. I now use it to cover the north bay window in this house. You could get a number of them to cover large areas of window and still be able to roll them up according to where the sun is so you do get light when you want. The bamboo shades last forever, I have had mine for nearly 20 years and they still look like they were just purchased with the exception of a little dust.