For many people even the slightest thought of going out somewhere to meet and make connections with people they do not know can be daunting. Whether it's due to time, resources, availability of meet-n-greet type opportunities, or your individual level of introversion, networking in order to meet other professionals in your journey to building your career can be very unappealing ~ rather than supportive of your long term career focus.
A few tips that are simple, quick and easy to do from the comfort of your office, on the train ride home, or from the comfort of your home, that can be as effective as in person networking as well as serving as a great follow up after meeting new people include:
Be sincere and work towards building relationships. When you least expect needing a contact is when you will see the results of the time and effort put in months /years earlier.