Originally Posted by oatw13

The very nature of blackout curtains will cause the room to become warmer. Because they are so thick, they are also insulating. Perhaps you could find a small, quiet desk fan to use also.

For yardage, I usually measure the window then get twice the width of the window by the length I want - usually I get at least a foot longer than the window to allow for tabs or a casing.

This may sound crazy, but a large chip clip or a large hair clip (the butterfly kind) both work well to hold a curtain back if you can't attach anything to the wall. Cheap, too! Otherwise, your 3M hooks and ties should work.

Good luck!