1) Participating in Kaggle competitions and MOOCs helped the speaker gain new data science skills in R, Python, and machine learning techniques. 2) This led to new opportunities like collaborating with other data scientists, presenting at meetups, and eventually getting jobs at data science companies like Domino Data Lab and H2O.ai. 3) The speaker's networking and side projects through Kaggle also allowed them to learn non-technical skills and expand their professional network, which further supported their career transition to data science.