Put a Little Lump in Your Tarp: You say there are no grommets in your tarp? Find some small round stones, some acorns, or even a couple of hard clumps of dirt, each about the size of a marble. Place one under the tarp edge, fold the tarp down around it, and then twist some line around that so the whole thing resembles a head and neck. This is called "choking the chicken." Now tie the cord around this neck and tie the end to your stake.
— Yankee Magazine Vinegar, Duct Tape, Milk Jugs & More by Earl Proulx, The Editors of Yankee Magazine