I have to congratulate you to your decision of making your life better. It's good that you approach strangers and ask them things and that you can have a conversation with them. You could have approached that guy with the jacket if you wanted. It wouldn't have been awkward, if you could have acted naturally.
There's one way to improve your social skills: Go outside and talk. Talk with all people around you: your bosses, your friends, your secretary, your family, the cashier in the supermarket, ...
Try to meditate and have a strong inner self-confidence. You have to have a strong identity. How is your outer stuff (your routines, your skills) gonna be congruent with your inner self if you don't have enough confidence.
Read books about that. Meditate. Think about life, and yourself. Relax. Look up for some "alpha healing sound" on youtube, as I find it to be very relaxing.
Trust me. I don't have a very strong self confidence. (Mine was destroyed from outside factors) When I started PU, I couldn't stand up and tell a stranger my opinion. That is very important!
Good luck bro
