If you can't get your self to take action (ex. walk up to a girl and say hi), you need to desensitize yourself from that fear and anxiety. This involuntary response of anxiety in your brain stems from past experiences when approaching strangers, or more likely, missing information about how strangers react to you approaching them. All you have to do to "rewire" that part of your brain is to associate approaching with good emotions. Try out some low-risk approaches (I like to call them "throw-away sets") to get used to the initial approach. You will truly feel good about approaching people because you believe you will give them a good experience. Here are a few things to can do today:
1. Ask for a quick opinion on something. Something that you actually want to know (ex. Hey quick question, you look my age, is taking 4 years to get my associate degree from here average? or Did you hear about that music festival this week? I see tickets are $200 now. Is there anywhere to get discount tickets?)
2. Tell someone a joke.
3. Honestly tell them you are taking part in a "self-help/self-development thing" (hey, that's true) and your mission today is to ask for peoples names and something interesting about them.
The takeaway from this post is. Freedom of outcome. Do not linger. Value offering. Understand that you are adding something to their day, not taking something from them. When you truly believe this, it will show in the smallest details like body language and eye contact and manifest into a great interaction.