Pins are items that you can wear on your lanyard so when people click on you it will display the 15 selected Pins and FX you choose.
To wear a pin click the pink couch icon on your user bar then select the Pins tab in the inventory pop up screen. In the top box is a list of all your pins to wear one just double click it. Also note you are only allowed to wear 15 Pins and FX
To remove pins click the pink couch icon on your toolbar then select the Pins tab in the inventory pop up screen. In the bottom box shows all the pins you are wearing to take one off just double click it.