- Win as many battles as you can. Each victory increases your trainer level, which is one of the factors that determines the number of stars on your card.
- Catch as many Pokémon as you can. The more Pokémon you catch, the higher your Pokédex count will be, which also contributes to the number of stars on your card.
- Train your Pokémon to a high level. The higher the level of your Pokémon, the more likely you are to win battles and earn trainer points.
- Complete side quests and challenges. Many of the side quests and challenges in Pokémon Sapphire offer rewards, such as trainer points, that can help you increase your star rating.
- Visit Mr. Goodshow every once in a while. He will rate your trainer card and give you advice on how to improve it.