It is mostly practice. You don't become less awkward, you learn it, and if you don't use it, then you'll lose it too. This is important because however you choose to practice engaging, needs to be sustainable for you. Drastic things that you can't keep up are probably not going to give you lasting results.

I recommend taking a bar job, maybe part time. I did that for some time and found my ability to deal with these situations improved dramatically, through the practice of talking with folk at the bar.