We prefer a multi page .pdf showing…
Page 1.
A composite image showing the special finish and the print.
Page 2.
A ‘print only’ version of the artwork, with the special finish removed – but not ‘knocked out’.
Page 3.
The special finish, be that foil or spot UV etc. In black!
There are variations to this for multi-page documents, double sided cards, pages with no UV, pages with UV, etc.
A further example might be
Page 1, the composite print.
Page 2, the print part
Page 3, the foil part
and this file is the complete 3 page .pdf example including bleed 
.
Your designer should understand the above, and you’re always welcome to give us a call for advice!
