This is much better than using giant buttons which have very limited visibility.
My friend claims he had perfect vision out of his button eyes, while mine minimally hurt my vision (the prescription lenses had different clarity depending on what angle I was looking out of them).
Step 1: Materials
If making non prescription lenses, either use plexiglass or you could potentially find pre-cut glass circles (used in photography I think).
Dremel tool with a sand grinder
Black Model Magic air dry clay by Crayola
soapy water (should be in a spray bottle, but I just dabbed it on)
Exacto knife or box cutter
Circle cutter or compass
Hole punch (1/8'' hole)
Limo tint - can be bought in huge rolls, but you possibly could find some scraps at a place that tints windows or on ebay. Or PM me. I have a huge roll and I could potentially ship you some if you pay for shipping.
Step 2: Circle Cutting
After sizing, get your roll of masking tape and cut 4 circles that are the same size out of it (Use a wide masking tape for this. I cut my circles right on the roll).
If you are making your eyes out of plexiglass, put the 2 circles facing back each other on each side of the plexiglass. Then score around the circles (I scored straight lines many times and broke off the scored parts. If you know how to score and punch out a circle from plexiglass, I'd like to know how to do that.) Use the dremel tool to grind down the plexiglass until you get to your masking tape. The masking tape acts as both a guide and a scratch protector. The plexiglass will smell and melt a little when you grind it, I suggest good ventilation.
If you are making your eyes with glasses, make sure you label each lens (Left and Right) and possibly (before you pop them out of the glasses) what side is up (I kind of wish I did the second part on mine). Put your masking tape circles on your lenses (one circle on each side) and grind your glasses down with your Dremel. The glasses will not smell when you grind them, but they will produce a lot of dust.
Step 3: Turn Your Limo Tint Into Buttons
Use a piece of masking tape and draw your circle on it. Draw four lines on the masking tape to make a square that is centered in the circle. The corners of the square will be where your button holes will go. Use your 1/8'' hole punch to punch a hole at each corner. Stick your limo tint to your tape and punch the same holes in the tint.
Step 4: Applying the Limo Tint
Use 2 pieces of tape (one on each side of the limo tint circle) and pull the tint apart from the clear plastic it is sticking to. Put your tint sticky side down on your lens/plexiglass circle.
Try to get as many bubbles out as possible. If you are using a curved rx lens, there will be 'mountains' of tint. If you use the plexiglass, the tint will lay flat.
Use the heat gun to shrink the tint to the lens. If your tint shrivels up a lot or you don't like the way it came out, you can try again with new tint.
Step 5: Adding the Edge/rim to the Button
Wrap the snake around the button eye and shape with your fingers.
You should put more of the clay snake on the front of the lens and then pull it toward the rear.
You'll have to keep shaping this with your fingers until you get a smooth edge and a smooth join.
After it dries, I suggest using some sort of glaze or clear paint on the back of the clay to prevent it from coming off or melting if you sweat a lot.
If you could find some rubber rings to fit snuggly against your lenses, I would recommend trying that. Smaller hardware stores sell individual rubber rings of various sizes. It would be perfect if you could find a rubber ring that was cut on the inside so that it would wrap around the lens.
Edit: One thing I forgot to mention - Add a bit extra clay to the back of the button eye if you are using flat glass or plexiglass. Otherwise, the button will hit your eyelids/eyelashes depending on your eye shape.
Step 6: How to Wear?
Put spirit gum where you want the button eyes to stick. WAIT until the spirit gum gets tacky and the solvent in it evaporates or you will get an eye full of fumes.
If for some reason, you don't like the idea of spirit gum, or if you just can't get it to stick, I used cut-up Command strips for my friend. They stick pretty well and are easily removable.
If your button eye gets spirit gum on it, either use the remover or some alcohol wipes to get it off. Don't bother removing it from the clay, you'll just end up dissolving the clay.