This is what I do when I want a quick diffuser for a pop-up flash. I use a 4ply piece of 100% cotton rag mat board cut to size and put it in the spot the flash itself collapses into when not in use, fits perfectly and stays there snugly.
This is a series of test exposures made on a Nikon D50 with a Sigma f/1.8 lens. Every file was shot as a Nikon RAW file and edited in Adobe Camera Raw.
This is a 14 minute 55 second long video demonstration that shows step by step how to dry mount a print without a mount press using a regular home iron. it is very simple and can be done without much hassle. video includes: spoken in English, background music everything needed is shown and listed.