You have to be methodical while doing this. You need to follow a process to become SEO. You must:

1. Be sure of your career objective. You must be certain that you are interested in SEO and in the field of digital marketing.
2. Complete your research about your career as SEO and the future scope of this career and be satisfied with it.
3. Educate and train yourself thoroughly for becoming a successful SEO.
4. Start a job or start a Do It Yourself program.
5. Build a very strong personal brand.
6. Keep in touch with people. Build up a strong network.
7. Exhibit your skills and offer them for others.
8. Never stop learning and do new things by experimenting regularly.