For sometime, I have been using folded sheets of paper as light diffusers. It was fine for the time being but it was really annoying to work with. I ended up building new diffusers out of cereal boxes, sheet protectors, tracing paper, and tape.
First, cut the front and back panels of the cereal box. Then, use the tape to reinforce the inside. It will collapse if you don't.
Then tape the sheet protector to only one side. Sheet protector works as a gel diffuser kind what professorial spotlights use.
The reason why I used a sheet protector is because, I can insert tracing paper to work like a diffuser. Also, I can use different color papers to make great lighting effects.
Test shot. It looks good but not great. I need to play with it more.
The cool thing about this, I can use it as a background.