Well, your tama must be an adult to use the items. After you buy an item, go to the ball and bat icon and press the middle button. It will give you 3 choices: GAME, SHOP, AND ITEM. Go down to ITEM and push the middle button. You should see your item. If you have more that one, press the button the the left side to scroll through them. When you see the one you want to use, press the middle button and your tama will use it! I highly recomend you buy the U.F.O. or the trumpet or the drum. They all make really cool noises! Good luck!
~Generation12