Instructions
Feed your Pokemon costly vitamin items such as Calcium, Iron and Carbos. Not only do these items greatly increase a Pokemon's happiness, but using these items permanently improves the monster's stats.
Walk with the Pokemon in your party everywhere you go. By walking 256 steps, a Pokemon gains additional happiness points.
Grow your Pokemon by leveling it up to make it happier. Battle often and against higher-level opponents to quickly add experience levels and happiness to the Pokemon.
Keep Pokemon from fainting in a fight. Other actions that decrease a Pokemon's happiness include feeding it bitter-flavored foods and trading it to another game.