I make my own custom holographic Pokemon cards with transparency film and vinyl decal wrap. I print them using my color laser printer.
Step 1: Stuff
Get the right transparency film for your type of printer. To give it the holographic effect, we use vinyl wrap.
Transparency Film for Laser Printers
Transparency Film for Inkjet Printers
TECKWRAP Aurona Craft Holographic Opal Vinyl Pack
Step 2: Artwork
You can get artwork by googling and other online resources. I use photoshop to customize and arrange them. I then print them inverted on my color laser printer.
Step 3: Trim Cards
To trim the cards use a sharp knife. Be very careful. I use a real pokemon card to help with sizing. Use a straight edge ruler for cutting.
Step 4: Attach to Real Pokemon Card
If the back will be visible like in a card holder I'll attach the holographic print to a real Pokemon card. Usually a energy card since they are abundant. You can use a bit of glue or double sided tape. It doesn't have to be affixed securely since it'll most likely be in a sleeve or card holder. Just enough glue/tape so it doesn't move around in the holder.
Step 5: Corner Rounder
You can use scissors to round the edges but it's best to use a corner rounder to make it consistent and clean. The one I use is the Kadomaru Pro, I use the smallest setting to cut the perfect corner.
Sunstar Kadomaru Pro, Corner Cutter
Step 6: Put in Card Holder
I usually put them in 1/4 screw down cases by Ultra Pro. You can put them in one-touch cases or even top loaders. What ever way you want to display your custom cards.
Ultra Pro 1/4" Screwdown Recessed Trading Card Holder
Ultra Pro 1” Thick Lucite Screwdown Trading Card Display
Step 7: Finish
So that's how I create my custom holographic cards for Pokemon/Hearthstone/Yugioh/etc.
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