Here's an example.
So, in the top left is the original card that my elder daughter sent me. No-one was more surprised than she that it arrived on time. To the right are three pieces I cut from the original using a guillotine; I did have another piece with the three coloured stripes on, but it was too thin to use so I chucked it out. At the bottom are the same three pieces with the corners rounded (using a corner-cutter, cheap from the Internet) and a hole punched (likewise).
It's amazing what a differerence rounding the corners and punching a 2mm hole makes. Apart from the fact that "Happy Birthday" is a bit too low, those look as if they could be professionally-produced gift tags. I can now be a cheapskate and no-one need know.
OK, so obviously you will know if you receive something with one of these three tags in particular on it, but I have more...