There are alot of things depending on what you like and how old you are?
Do you like any sports? Join a basketball team or something. In New Zealand we have girls teams to so there are always alot of babes around.
I am quite young so I go out clubbing to raise my social value but it is the same old and can get boring when you are older. I would recomend that you join a gym. Not only would you get in shape but you will meet alot of great people that have great advice. Again at my gym in NZ there are HB's that go there haha. Generally going out with your mates more will help also just go and do stuff and try to be busy all the time doing things and that will make you look like you are busy and have a social life. If you like cars join a car club. Think about your town area and what there is to do often and ask others what they do you might be surprised. Try to take women out reguraly if possable. Always be open tommeeting new people and be nice to them.
In the changing rooms I made good conversation with an old guy while he dropped his jocks haha. He was a swimming coach and gave me a free lesson because I was freindly and presented interest in swimming. I can now swim twice as much lenghts now. You might need a wing man to help you meet new people if you don't like going out by your self.