You administer training when your Tamagotchi beeps.
When it beeps, check its status. If its status seems OK, and the character is just bouncing around on the screen, go to the sixth option and select time out. Your character may get a bit unhappy, but it will get some training.
If it beeps and its at the bottom of the screen fuming or crying, select praise. Then it should smile at the bottom of the screen, and you will get one extra training bar.
Last of all, when you wrap a present, and you send it to another V3, sometimes it doesn't send that present, and can send a bad present (ghost, poo etc...). The sender will smirk at the bottom of the screen. Time it out to tell him he must give the present.
When your character is a baby, after 35 mins or so, it begins to cry at the bottom of the screen, select praise then too, that is your first training bar! :furawatchi: