Central retinal disease in the form of age-related macular degeneration is now the leading cause of vision loss in persons over the age of 65 in industrialized nations.
First you have to distinguish between the optics of a wrap glass and the mechanics of the same.
The optics pretty well covered above.
For the mechanics, try only thinking about a lens with a...
Make sure the fresnel is smaller than the lens you applying it so it doesn’t touch the frame. Add a few drop of dish detergent to the water it will work wonders in eliminating bubbles.
Another trick, works on all lenses, but particularly higher curves as well. Use HOT water. Not boiling, but hot enough you immediately notice if you put your hands in. That will soften the flat...