Applying foil to prints is simple.
First of all, three files are required. There should be a file showing how to create it.
This document should be the complete design of your card, showing the foil area/location.
2. Print Artwork
This document should only have the areas printed with CMYK Ink (not including the foil)
3. Foil Artwork
This document should include only the areas for foiling(100% Black)