I store ALL my yarn in these clear plastic zippered bags.
This is a size medium bag...and you can see how much yarn it will hold. I also use the small bags which will hold 10-15 skeins of dk or worsted weights.
I get them at www.woolworks.com
and they are not expensive. CLICK HERE
It is good to keep your yarns in zippered bags to prevent moths and spiders, etc. from setting up shop!