To form the single crochet stitch, insert your hook through the center of the second chain from the hook. Remember the loop ON the hook does not count as a stitch. Wrap the yarn around the hook and pull it back through the chain. Wrap the yarn around again and pull it through all the loops on the hook.
When you have reached the end of your first row, chain 1 and turn your work. Insert your hook under both loops of the first stitch, wrap the yarn and pull through the stitch. Wrap the yarn again and pull through all the remaining loops. Continue working this way until your piece is as long as you like.