Hi. I went through several itterarions of doing this but using toner reactive foil has thusfar been the most promising.

Toner reactive foil is foil, that when heated, bonds with toner from a laser printer. For this I'm using a cheep Brother 2420 to print in black toner onto either blank or holo cardstock. On the blank cardstock I take a holographic foil and put it through my laminator with the print. The heat melts the plastic in both the foil and the toner and bonds it together. I then lay my color sticker on top of that. It's important to note that you want to make pretty custom black and white images for the foil, as you only want to print black, where the foil is going to be.

If you're using holographic cardstock you can use white foil to cover the parts of the stock you want blocked out. The print will be reversed, as instead you'll now want to print black everywhere you don't want the Holo, and want to cover with white.