For this project I found online images of target silhouettes, then created a small card template in an image editor. I printed off a few and took them to the rifle range and set them up as targets. You could use any calibre or cartridge you like, but since these cards were so small I chose to use a .22 rimfire cartridge as it's small and easily aimed.
Of course, you don't have to bring your cards to the range to create holes. You can simply poke holes with a sharp pencil and get almost the same effect (though doesn't have the impact fatigue that ammunition does, is still very convincing).
If you wanted to make your own I've also included a PDF scaled to A4 (8.5" x 11") that you can print at home, along with the silhouette card and font template. You are free to modify and scale to make your own custom version.
Have you made your own I miss you card? I want to see your results! Share a picture or video with your version of this project in the comments below and you'll get a digital patch and a 3-month Pro Membership to Instructables!