1. Launch the game and select the first level to start playing.

2. The objective of the game is to guide Red boy and Blue girl through a series of levels and collect diamonds along the way.

3. Use the arrow buttons on the left side of the screen to move Red boy, and the arrow buttons on the right side of the screen to move Blue girl.

4. Work together to solve puzzles and avoid obstacles in each level. For example, Red boy can push buttons that open doors for Blue girl, while Blue girl can swim through water that Red boy cannot.

5. Collect diamonds in each level, which can be used to unlock new levels and characters.

6. The game is designed to be challenging, so expect to die a lot and try to learn from your mistakes.

7. Look out for power-ups that can help you progress through the levels, such as fireballs that can destroy obstacles and shields that protect you from enemies.

8. Keep track of your score at the top of the screen, and try to beat your high score as you progress through the levels.

9. Progress through the levels and try to unlock all of the characters and achievements.

10. Remember to communicate with your partner and have fun working together.