I promised never to do this - BUT only for you needy folks when I have nothing else to do. And Dave's basically a good person though not as needy as most really needing this stuff.
1) Ensure internal Gerber data really matches board and stencil (Gerber is dumb data only indicating x/y stuff)
2) Email or whatever away to supplier with instructions and a drawing derived from your CAM/Gerber output - color coded or whatever to indicate special requirements as step downs, etc.
3) Do business with suppliers only having internal inspection capabilities based on CAM input (Gerber data to internal AOI)
4) Receive stencil for visual inspection especially looking for damage (pits, dings, dents, etc.) and have very responsible engineering personnel, whoever that is, do visual to ensure PCB matching characteristics and features (fids, pattern locations, etc.)
5) Install stencil and board in printer and observe no "green" showing - only silver, gold, or whatever solder termination areas match stencil apertures perfectly, unless otherwise required/specified.
6) At the printer, print paste on mylar (ESD preventive of course) and inspect/compare to board - first before printing board.
7) Print first article, determine print quality, if acceptable, then go for it.
MoonMan
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