A chain sinnet is like making a chain out of loops with a rope or cord. You grab the rope, fold it in half, and make a loop at the top. Then, you take the end of the rope and bring it through the loop to create another loop. You keep doing this until you have all the loops you want. When you're done, the loops will stick together like a chain, and you can pull on the end to undo the whole thing. It's kind of like making a necklace out of macaroni, but with a rope instead!