These are the party bags at my curry fest.
I added measurements here to make it easier to explain. The packet can have wider gussets, and be sort of squarish in section, but once you have made one with my measurements you’ll understand how to adapt it.
Again, I added measurements so that it would be easier to follow. Basically the rule is this: The first horizontal fold which I did at 5.5cm needs to be wider than the side gusset (which is 4cm) The second fold (which is part of the 5.5cm measurement) needs to be the same width as half the side gusset. Then the packet can be folded flat very nicely.
VOILA! A great time was had by all!