Ok I'm not very good in explaining things LOL
But here are the "molds".The black one I used for the headlights on tne greif.I always have my eyes with me and pick up things with shapes that can come in handy when building models.
When I have found the right shaped thing,I cut the part out.
Glue the edges together and place it over the "mold" like this
And then it's just to bend the flips down to the right shape against the top of the "mold" And begin to glue one flip to the other one by one.
I hope this made some sence