>> 2. It also helps to be cheerfully unembarrassed about taking the lead in organizing groups to do stuff. People are often secretly grateful to be able to follow someone else. They'll often reject you. They'll say yes but then flake out on you. You'll feel mortified; you'll be certain that everyone else thinks you're a dork. That's OK; keep at it. (This is good practice for customer development and sales work, come to think of it.)
This is exceptionally true. I moved from Boston to Beijing a few years ago (and in with my girlfriend at the same time) and essentially had 0 friends for about six months. I'm not naturally very social, so of course, I became extremely depressed.
At some point, though, I got through it and realized that I needed to meet more people. I started a "Beijing Coworking" email list for anyone who was working on a startup or freelancing to meet in coffee shops every day. I literally planned out which restaurant I would be in every day for a week every sunday and emailed it out to 100+ people. Only 3-4 people came regularly, but some of them are now among my closest friends.
I also learned from one of them how to turn acquaintances into friends. She had an email list of cool people she knew, and would schedule random events a few times a week. She didn't care at all if people came or not.
She's since moved away, but now every time I meet someone, I add them to my contacts and invite the whole set of Beijing contacts out whenever I go to a concert or out to eat, etc. People who don't come to anything in the first three months get dropped, but even so, just losing the embarrassment of inviting people means I naturally give them a few more chances to become a friend.