I used to go out alone a few years ago regularly and I always got to know new people and women. I didn't have to approach or do anything, I was approached by groups or sometimes by women by just sitting on the bar and drinking my beer.
Sometimes I went dancing on my own and women would dance with me and then make out etc. One time I met a whole group and there was a woman I really liked and so did she but two guys were permanently cock blocking me, one of them kept telling me, that she was a "cheap whore". lol Another time I was sitting in a bar and drinking british ale and a blonde woman was secretely eye fucking me infront of her boyfriend until he saw it and got mad at her and then they left. The same night another woman bumped into me so rudely from the back, that it almost threw my glass away. So we talked and she invited me over indirectly to her table where her friend was waiting but unforutnately I had to leave soon. Two other times I made out with 2 girls who were looking and smiling at me but who had byfriends which I found out later that night. So many silly things happened.
So yeah, going out alone is the best you can do at times.