I'd say either buy a house to rent out or look into a stock broker. Getting into stocks by yourself is way too risky if you aren't doing it full-time, and even if you did start doing it full-time, you'd just be a small fish in a big pond.
If you do buy a house and rent it out, know that it takes a lot of work. My grandfather was into this business and a lot of weird shit happened. He rented out a lot of upper-middle class homes and a lot of low class homes and some crazy stuff would go down. He rented out one of his low class homes to a Hmong kid who was fresh out of college. A few months in, the kid brought his parents and grandparents over from the mountains in Asia and they slaughtered and roasted animals in the living room and pissed and shat all over the floor. It was fucking insane haha.