A littler different direction than your intention.
For years I've created art work (using Paint). Sized it and laser printed it on clear Acetate sheets. "Remember that stuff
from the old overhead transparency days?" In sample photo below the white letters POOL HALL were placed on a green background, cut to size then glued into each window opening. All the clear window signs were done this way. For a dirty rundown effect a shot of dullcote on the inside makes it.
Rosie's Bakery and El Cheapo Liquor were sized and color printed on paper then turned into a sign.
I always found it fun to look up images that might relate to your business on the internet. Copy and manipulate to your desire. The real challenge is to print (on paper), cut and fit and probably resize again. Once the size is right print using a color laser printer. An ink (jet printer) will not stick to acetate. It stays wet and smears. You won't believe the amount of art work you can download once you start looking......
Good luck
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