My advice, really, is not to force the issue.
Join clubs, especially those which emphasize your "special interest." Join an opera club, join an anime club, whatever. You'll find people with common interests.
Also: maintain a modicum of hygiene. Wear decent clothes (jeans and sweaters are great in the winter; you could get away with lots!) In the summer, polo shirts and chinos are the best. Don't wear plaid shirts!
I used to try to force things--I would be swatted away like I was a gnat. I'm a short guy, and I was immature when I was in my 20's. I had tremendous difficulty getting dates.
However, one day, I just walked into a bar, and started playing pool. I started having conversations with people. Ladies started having conversations with the people I played pool with. By osmosis, they all started having conversations with me.
I didn't get a date that night---but it increased my confidence.
Forcing the issue=gnat to the ladies