i have a chihuahua its old we estimated well its mean how do u train it????

hiển thị them a treat and say them to do somthing but they dont know what do do so bạn train them for exsample say bạn wanted it to roll over bạn do it first and it may do it and when it does a trick always give it a treat if it wont keep hiển thị it and soon it will do it