You can tell what someone believes by their actions. They can say what they believe all they want but if it doesn't match up with their actions then it's not what they really believe. If you really believe that God created the universe and cane down, gave His life for you, and we're all going to His home after we die then you will live your life differently. You'll put a priority on getting to know God. Yes life will get in the way because you're not perfect but you will try to get closer to God. If you try to follow all of God's commandments people will notice and I think it's one of the best ways to share your faith in God. When you act differently people notice, they want to know why you forgive easily, are filled with joy, are kind to everyone, doesn't get drunk. They'll be curious and it gives you a good opportunity to tell them about God without you having to go to them with the conversation. Look at your actions the past week and see where you are with God.