|from my Insta|
She found a free download of the "save the date" text here, then used a regular printer to transfer it onto the card stock.
Finally, measure the halfway point (2.5") to make holes near the edge of each side. String your 8" piece of cording or hemp through the holes, remembering to loop it once in the middle (it would be rather anticlimactic to pull open the card without there being a knot). Pop it in a color coordinated envelope and head to post office!
K mentioned that she found the fonts she used for free online. Downloading a few fonts can add a special touch, because no one wants a wedding invite in comic sans. Don't be afraid to pay for one if you love it- most I've seen are between $10-$100, which is pretty affordable considering how many uses you'll get out of it: save the dates, invitations, place cards, menus, programs, drink lists, even thank you notes. Some of my favorite free resources include 1001freefonts.com and dafont.com. Check out a few from that last source below: