Network is not something you get overnight. It may take years of strategic planning to achieve.

I would say networking is less about meeting people and more about building a reputation. Commenting here on HN is one way to build that reputation. You can get go to meet ups to meet people, but giving talks is how you get reputation. The same applies to conferences. At work, especially in larger companies, you can build reputation as experts in one particular technology, lead brown bag sessions to demonstrate that expertise.

You sometimes notice other people that have good network. It's also important to stand out in front of these people to get second degree connections. If you also have good network, these people would gladly be your best friend.