How to use your spare time to increase your income?

Tell me about my own experience, for reference only. After graduating in 2013, I joined a Japanese company and worked 8 hours a day. Working five days a day and two days off gave me a lot of spare time. At first, I just wanted to lose weight. I got a yoga card and started practicing yoga. I basically have 3-5 nights a week. I have been taking classes for 3 years. I have met very good yoga teachers and friends, and have learned to be a yoga instructor. I have been teaching classes since March 2017, and I am still learning. My suggestion is to choose something you like, and the most important thing is to stick to it. People's energy is limited. Only by focusing your limited energy on the same thing can you achieve corresponding results.