So far they're pretty durable, but you can also make an untrimmed version; I made a non-trimmed pair last night by folding under the corners of the headpiece, and since I wasn't cutting, I just used a darning needle and yarn to attach the earpieces to the headpiece.
This pair is slightly different, since I learned how to crochet in the round and join. You can't see it in the pics, but I also added little tassels to the ties. I did the headpiece the same way, but instead of doing the earpieces in a spiral:
-I made a magic ring and did 5 sc, joining with a slip stitch.
-Round 1: One ch, 2 sc in each sc, join with slip stitch.
-Rounds 2-3: One ch *two dc in the first sc, one dc in the next sc* repeat round, join with slip stitch.
-Round 4: One ch, sc in each dc around, join with slip stitch.
-make chain stitches until you have a tie about 8-12" long.
(I switched yarn on Round 4 to give these a green border to match the "One Skein Scarf" I made my mom, patter from D. Stoller's "The Happy Hooker.)