I used number mats. I let Ella jump on the numbers from 20 to 1 while counting backwards. You can make your own like TmT did:
http://forum.brillkids.com/teaching-your-child-math/printable-numberlines/msg59675/#msg59675 or you can buy one:
http://www.lakeshorelearning.com/product/productDet.jsp;jsessionid=N9dH2w5jnd9B1fdFy5JmRt855GhTGjrn414rWj2tLLprzvp61dBK!1403828257!49112879?productItemID=1%2C689%2C949%2C371%2C898%2C313&ASSORTMENT%3C%3East_id=1408474395181113&bmUID=1308433735122
You can also use it for teaching "counting on."