So, if you want to share the gospel, you have to be comfortable with being uncomfortable. I still misjudge situations and say the wrong things. I still feel awkward sometimes when someone says something harsh back to me. Just the other day, someone walked away from me. He didn't even say anything! We started talking, and he just walked away. I know that he wasn't rejecting me, but it felt that way. One the flip side of being nervous, feeling awkward, and getting rejected, you might see people put their faith in Jesus. Sometimes the reward can be much bigger than the feeling of nervousness or any rejection you might face.
All the people I've ever known who started sharing the gospel had to be uncomfortable for the first few times. After that, they always end up telling me that it wasn't that hard. After they get over their initial fear, they're excited and ready to try it again. They would all tell you that you're missing out if you're not sharing your faith." 
Courage and Godspeed,
1. James Boccardo, Unsilenced: How to Voice the Gospel, p. 48-49.