Instructions
Go to Route 230, which is marked on your in-game map. Walk among the tall grass until a Togepi attacks you.
Fight the Togepi as you would any other Pokemon. Stop attacking it when its health bar turns red. Select your Pokeball from your items list and catch the Togepi.
Walk around with Togepi in your inventory, not in your deposit box. This will raise its happiness. Once you have taken 2,816 steps with Togepi in your inventory, it will hatch and evolve into a Togetic.