I use bits of yarn left over as stitch markers.
I've learned that if you are knitting in Magic Loop and you separate the stitches with the working yarn on the back needle, you'll always know when you are at the beginning of a round because the working yarn will end up at the beginning of each round!
Knitting/Crochet/Crafting/and Related Product Review Blog: KnitPurlGurl
"Yarn stashes insulate the house."
"Just one more skein can't hurt."
- from Knitticisms