How do you get zombies on zombie farm

You have to got o the right corner of the screen and click on the symbol. Then you have to click on the shopping bag that is one of the sybols shown up. Next you should be looking at your crops that you can buy, the word "Crops" is lit up on top of the crops next to it says "Zombies". Click on zombies and then pick a zombie that you like, next you press "Buy" Then you will be back to your garden and you click on the dirt spots and your person starts to plant it.