How can I change this?

There's this guy I really like but I have a fear of talking to people other than the normal "hi, how are you". Being afraid is making it really hard. 
 today we went on a hike, we were out from 930 to 12ish and we barely spoke. It took me 20ish minutes to get the courage to ask one question. 
How can I tell him that I'm afraid to talk without him thinking I'm weird?