I just got my chicks this morning and have been teaching them to use their water bottle too> I got a hamster bottle for mine, but it's the same principle of click it and drink. I took each of them one at a time and gently pushed their beaks into the ball (or nipple in your case) and once they felt the water on their beaks they drank it and tapped it themselves. One of the chicks got the idea just by watching me flick it with my finger and some got curious watching the others drink and tried it themselves. All in all, I've only had them a few hours now, and five of six are pros. The last one will get it soon I'm sure.