You can sew the design that has been optimized for mylar without using mylar but you may not like the results. Be sure to scroll down to see all of the pictures and the explanations.
This leaf is a regular filled design.
We put a piece of mylar behind it but you can see that the rows of stitching are too close together to let you see any sparkle in the design.
Notice that the leaf is orange and the stem is brown.
This is the same leaf optimized for mylar. You can see that the rows of stitching are much farther apart.
We did NOT use any mylar with this sew out.
Notice that you can see the background fabric through the stitching.
The design looks very "flat" because the threads are not close enough together to give it a nice filled color.
This one was sewn with the same orange and brown threads as the first one.
This is the same leaf as in the sample above but with a sheet of Opal Iridescent mylar behind it.
Light hits the mylar between the rows of stitching and you see sparkle instead of background fabric.
Opal Iridescent mylar provides the shine but the color comes from the thread that you use.
We used the same orange and brown thread on this sew out.
This photo has not been retouched or enhanced in any way.
This is the same leaf as the one above but this time we used metallic mylar behind the leaf.
These bright colors of mylar completely block the background fabric and they dominate the color of the finished design.
If you look closely, the leaf and stem are done with the same orange and brown threads as the previous design but you really don't see that.
You see the color of the mylar rather than the color of the thread.
This can give you spectacular results for some designs but you would not really want to have a single color of metallic mylar under an entire design unless it is like this leaf - all one color.
For this design, we layered the colors of metallic mylar for a special look.
We used a green metallic mylar with green thread, sewed out the first color, then tore off the excess mylar.
Then we laid down a sheet of red metallic and sewed with red thread. We then tore off the excess mylar when this color stop was finished.
Then we laid down a gold metallic mylar and used gold thread.
This technique takes longer but can give you spectacular results.