The first step to harmony is understanding and acceptance. It's important to realize that each of us is unique, and our differences make us interesting to each other. If your partner is more relaxed, it doesn't mean that he's less interested in the relationship. He just has a different rhythm of life.

Compromise is the key to a successful relationship. Find a middle ground that suits both of you. For example, if you like active recreation, and your partner prefers quiet evenings at home, try alternating these types of leisure activities. On one weekend, you can go for a walk or hike, and on the other, arrange a cozy evening with movies and delicious food.
Open and honest communication helps to avoid misunderstandings. Discuss your needs and desires, and explain what is important to you. Perhaps your partner doesn't even realize how much you need activity or, conversely, peace and quiet.
Support each other in their aspirations and interests. If your partner likes quiet evenings, try to find something pleasant in it for yourself. For example, you can take up reading, drawing, or any other hobby that brings you joy. And if you like outdoor activities, invite your partner to try something new with you.
Don't forget about the importance of personal space. Sometimes we need time alone to recharge and gain strength. This is normal and even good for a relationship. Respect each other's needs and give each other the opportunity to be alone with themselves.

Different temperaments are not a sentence, but an opportunity for growth and development. It's important to remember that our differences make us stronger and more interesting. Find a balance, support each other, and don't forget to communicate openly. Then your relationship will be strong and harmonious, despite all the differences.