Hi James,<br><br>The secret to folding so as to not create a lot of pressure at the fold corners is to fold your foil like a road map rather than a tarp. Meaning, folds that are zig-zag shaped or fan shaped put less pressure on each fold. folding the foil over and over onto itself, on the other hand, tend to bunch the foil up at the corners and will eventually split the metal. It is had to describe the difference but just look carefully at how a road map is folded and you will see what I mean.<br><br>David Koelzer