To ensure that this guide was made to the best standard I had it verified on Pyroguide, ideally I should submit it to the wiki. So here is a guide to making flash powder (which I wrote):
In my pyrotechnics group scroll down to the comments
If you want to view it on Pyroguide then here's the link to it:
How to make fireworks, rockets, compositions and other pyrotechnic devices, etc. Making fireworks> Third page > Flash tutorial. Pyroguide has one of those funny linking things where it remains at the directory.
Comments? Questions?