When in a romantic relationship, boys doing thoughtful and caring things usually make girls feel happy. 

Here are some suggestions:

1. Listening: Carefully listen to the other person's thoughts and feelings, and let them know that you care about them.

2. Concern: Concern about the other person's daily life and trivial matters, and inquire about their daily life and emotions.

3. Surprise: Prepare surprises on special days (such as birthdays, anniversaries, etc.) to make her feel valued.

4. Accompanying: Spend time with each other and spend good times together.

5. Help: When she needs help, do her best to provide support.

6. Praise: Praise the other person's appearance, talent, and personality, allowing them to feel your appreciation and affection.

7. Respect: Respect the other party's choices and decisions, making them feel their importance.

8. Honesty: Honesty is the foundation of love, allowing the other party to feel your sincerity and trust.

In short, making the other person feel your love and care is the key to making people happy when doing various things.