how to be more comfortable situations

I've very shy and insecure and everytime I'm with people I just met I just sit there with my mouth sut but I want this to change. Any tips?

*SORRY I MEANT HOW TO BE MORE COMFORTABLE IN SOCIAL SITUATIONS :$

estranged, I think that is brave to want to change your social behavior. I kinda think you already know what you have to do to be more social.Can you start with small talk;
Just asking someone how they are. Maybe getting into the flow of conversation and adding your thoughts and words on topics. I use to do a lot of listening too when I was young; and it seemed sometimes people can talk over each other rather rudely.
Often time a good listener is real value over a big talker. Being paid attention to
by a talker is a "feel good" for them.
hugs, bj

I talk to strangers; start a conversation with the clerk at the store? Just ask when they get off or tell them about the weather outside (large grocery stores without windows are good for this :-) or if you overhear the clerk and person in front of you talking about something, look at them and smile/laugh at something funny one of them says, etc. You won't see them again or be "recognized" if you do and it is an easy way to get a little comfortable realizing that what you say does not have to be earth shattering or very clever but just friendly and that people are more than happy to be friendly toward you.