ID badges serve a similar function no matter how they're used: to identify the person wearing them. You don't have to spend a lot of money to make a great ID badge, and the paragraphs that follow will highlight ways that you can inexpensively make your own badges.
Use card stock, which is heavier than paper so it holds up better when laminated. You can use any kind of card stock; the 90 pound works just fine and you can buy it at many office supply chains for around $12 per 250 sheets. That will make a lot of ID badges.
You will also want to grab a roll of clear contact paper, as this is what you'll use for lamination. You can buy this anywhere that contact paper is sold for about $4 to $6. To cut contact paper, you use just regular scissors.
Finally, invest in a bag of pin backs so that users can wear your ID badges. They're about $2 to $3 for a bag of 60.
You can make your badge any size you would like, but they are typically about the size of a credit card (2 1/2 inches tall by 3 1/2 inches wide), and you can use all kinds of word processing or page design software for layout, or you can download a template from Microsoft Office Online. Type into the text space the information you would like, which depends on the function the card will serve, add any images and colors that you want, and print. If you would like more than one badge, use your software's copy and paste functions to create multiple badges and edit each one for content.
Once you have printed your badges, cut them out and lay them on a flat surface face up. You will want to unroll your clear contact paper and cut pieces twice the size of the height of each badge, so that you can wrap the contact paper around the front and back of each badge. The contact paper is peel and stick, so it's easy to use. Place the badge along the bottom of the peeled, sticky-side up piece of contact paper, leaving about a 1/4 inch from the edge of the paper to the bottom of the badge, and fold the top half of the contact paper down over the badge. Press the contact paper flat against the card, making sure to avoid wrinkles, and seal each side by rubbing with your finger. Trim off the excess contact paper.
Dab hot glue on the pin back and stick that to your ID badge.
You can also purchase badge holders and attach to any strap or string for wearing around your neck, but this will cost a bit more.